2018年电大可编程控制器应用期末复习模拟试卷及参考答案

可编程序控制器应用试题答案及评分标准 第 1 页（共 14 页） 电大可编程控制器应用期末复习模拟试卷及参考答案一、填空题（每空 2 分，共 30 分）1. PLC 的输入/输出继电器采用 八 进制进行编号，其它所有软元件均采用 十 进制进行编号。(八 十)2. PLC 的状态元件中 (S2S9) 用于初始状态。(S2S9)3. 描述 PLC 的主要技术指标有 、 、 、 、 和特殊功能模块六种。(I/O 总点数 存储容量 扫描速度 内部寄存器 编程语言与指令系统)4. PLC 的输出形式主要有 输出、 输出和 输出三种。(继电器 晶体管 晶闸管)5. 说明下列指令意义。 MOV RST ORB LD (数据传送指令 复位指令 串联电路块的并联指令 取指令)6、可编程序控制器采用微处理器作为中央处理单元，可以对 进行控制，也可以对 进行控制。 (逻辑量 模拟量)7、PLC 具有逻辑运算功能，能够描述继电器触点的 和 等各种连接。(串联 并联)8、PLC 具有 和 功能，完成对模拟量的控制与调节。(模数转换（A/D 转换） 数模转换（D/A 转换）9、按结构形式分类，PLC 可分为 式和 式两种。(整体式 模块式)10、 模块是可编程序控制器系统的运算控制核心。(CPU)11、 是安装可编程控制器各类模板的机架，可根据实际需要选择。(导轨)12、 模板用于对 PLC 内部电路供电。(电源)13、 是用来将输入端不同电压或电流信号转换成微处理器所能接收的低电平信号。(输入电压转换)14、输出电平转换是用来将 控制的低电平信号转换为控制设备所需的电压或电流信号。(微处理器)15、 是在微处理器与 I/O 回路之间采用的防干扰措施。(电气隔离)16、S7-300/S4-400 可以通过 接口组成 PLC 网络。多点接口（MPI）17、MPI 是 的简称，MPI 网采用 的通信模式。 （多点接口 全局数据（或 GD） ）18、全局数据（GD）通信方式以 分支网为基础，是为循环的传送少量数据而设计的。 （多点接口（MPI） ）19、 通信方式以 MPI 分支网为基础，是为循环的传送少量数据而设计的。 （全局数据（或 GD） ）20、可编程序控制器系统中，主站之间的通信方式为 ，主站与从站之间为 ，以及这两种方式的混合。 （令牌方式 主从方式）21、PROFIBUS 网络由 、从站、 等构成。 （主站 网络部件）22、DCS 是 的简称，由单回路仪表控制系统发展起来。 （集散控制系统）二、简答题（每小题 5 分，共 20 分）1. 简述 PLC 的硬件结构和软件系统1.答： PLC 采用了典型的计算机结构，硬件主要由微处理器（CPU） 、存储器、采用扫描工作方式的 I/O 接口电路和电源等组成。PLC 的软件系统由系统程序和应用程序组成。2. 什么叫扫描工作方式？什么叫扫描周期？它主要受哪些影响？2. 答：与其它计算机系统一样，PLC 的 CPU 是采用分时操作的原理，每一时刻执行一个操作，随着时间的延伸一个动作接一个动作顺序地进行。这种分时操作进程称为CPU 对程序的扫描。PLC 的用户程序由若干条指令组成，指令在存储器中按序号顺序排列。CPU 从第一条指令开始，顺序逐条地执行用户程序，直到用户程序结束。然后，返回第一条指令开始新的一轮扫描，这就是 PLC 的扫描工作方式。除了执行用户程序之外，在每次扫描过程中还要完成输入、输出处理等工作。扫描一次所用的时间称为扫描周期。扫描周期的长短，首先与每条指令执行时间长短有关，其次与指令类型及包含指令条数的多少有关。3. 可编程控制器梯形图编程规则的主要内容是什么？3. 答：梯形图程序编程的基本原则包括：（1）梯形图中的阶梯都是始于左母线终于右母线。（2）接点应画在水平线上，不要画在垂直线上。（3）并联块串联时，应将接点多的支路放在梯形图的左方。串联块并联时，应将接点多的并联支路放在梯形图的上方。（4）不宜使用双线圈输出。可编程序控制器应用试题答案及评分标准 第 2 页（共 14 页） 4. 为什么称 PLC 的内部继电器为软继电器？和硬件继电器相比，软继电器的触点在使用上有何特点？ 4. 答：PLC 内部的继电器并不是实际的硬继电器，而是 PLC 内部的存储单元。因此，称为“软继电器” ，梯形图是由这些“软继电器”组成的梯形图控制线路图，它们并不是真正的物理连接，而是逻辑关系的连接，称为“软连接” 。当存储单元某位状态为 1 时，相当于某个继电器线圈得电；当该位状态为 0 时，相当于该继电器线圈断电。软继电器的常开触点、常闭触点可以在程序中使用无数多次5、传统继电器接触器控制系统和可编程控制系统有何区别？答：传统继电器接触器控制系统为“硬接线”程序控制系统，通过修改控制器件和接线来改变控制功能；可编程控制系统为“软接线”程序控制系统，通过修改 PLC 程序并改动少量接线端子来改变控制功能。6、简述可编程控制器的特点。 答：高可靠性，应用灵活，编程简单，但价格较高。 （详细解答也可）7、可编程控制器的性能指标有哪些？ 答：衡量 PLC 的性能指标分为硬件指标和软件指标。硬件指标包括环境温度、湿度、抗干扰能力、使用环境和输入输出特性等；软件指标包括扫描速度、存储容量、指令功能和编程语言等。8、可编程控制系统与工业控制计算机、集散控制系统的主要区别在哪些？答：工业控制计算机适用于要求快速、实时性强、模型复杂、计算工作量大的工业对象的控制；集散控制系统在模拟量处理和回路调节方面具有优势，主要侧重于回路调节功能；可编程控制系统在数字处理和顺序控制方面具有优势，主要侧重于开关量顺序控制，具有很高的可靠性和抗干扰性。9、简述可编程控制器的基本结构及其各部分功能。答：（1）导轨：安装 PLC 各类模块的机架；（2）电源模块：用于对 PLC 供电；（3）CPU 模块：CPU 模块为系统的运算控制核心，根据系统的程序要求接收并存储用户程序和数据、现场输入设备的状态和参数，诊断 PLC 内部电路工作状态和编程过程中的语法错误，完成用户程序规定的运算任务，更新有关标志位的状态和输出状态寄存器的状态，实现输出控制和数据通信等功能；（4）输入输出模板：连接 CPU 模板与现场输入输出元件或设备。10、PLC 配置电气隔离的作用是什么？ 答：电气隔离是在微处理器与 I/O 回路之间采用的防干扰措施。11、西门子（SIEMENS）公司有哪些主要系列的 PLC 产品？可以采用哪几种编程语言？答：西门子（SIEMENS）公司主要的 PLC 产品有早期的 S3 系列、S5 系列和当前的 S7 系列。S7 系列可采用的编程语言如下：（1）梯形图（LAD） ；（2）语句表（STL） ；（3）功能块图/逻辑功能图（FBD） ；（4）标准控制语言（SCL） ；（5）顺序控制（S7-Graph） ；（6）连续功能图（CFC） 。12、集散控制系统和可编程控制系统有何区别？ 答：集散控制系统在模拟量处理和回路调节方面具有优势，主要侧重于回路调节功能；可编程控制系统在数字处理和顺序控制方面具有优势，主要侧重于开关量顺序控制。13、工业控制计算机和可编程控制系统有何区别？ 答：工业控制计算机适用于要求快速、实时性强、模型复杂、计算工作量大的工业对象的控制；可编程控制系统具有很高的可靠性和抗干扰性。14、在 PLC 控制系统设计中最为重要的原则是什么？答：在 PLC 控制系统设计中最为重要的原则是满足控制对象的控制要求、确保控制系统的安全可靠性、简化系统结构。三、请写出以下指令表对应的梯形图（每小题 8 分，共 16 分）1 LD X000OR Y001ANI X003ANI Y002OUT Y001LD X002OR Y002ANI X003可编程序控制器应用试题答案及评分标准 第 3 页（共 14 页） ANI Y001OUT Y002END1.2. LD X000OR X001LD X002AND X003LDI X004AND X005ORBOR X006ANBOR X003OUT Y000END2. X000 X003 Y002Y001Y001Y001Y002X002 X003 Y002X000X001X002 X003X004 X005X006Y000可编程序控制器应用试题答案及评分标准 第 4 页（共 14 页） 3.LD I0.1A I0.2AN I0.3= M0.0LDN I0.1O I0.2O I0.3A I0.4NOT= M0.1四、请写出以下梯形图对应的指令表（每小题 10 分，共 20 分）1.1 LDI X0 AND X1LD X2ANI X3ORBAND X4X003可编程序控制器应用试题答案及评分标准 第 5 页（共 14 页） LDI X5AND X7LD X6ANI M3ORBANBANI X10AND X11OUT T0K100AND TOOUT Y222. LD X000SET S20STL S20OUT Y000LD X001SET S21STL S21OUT Y002LD X002SET S22STL S22OUT Y003LD X003SET S26STL S26可编程序控制器应用试题答案及评分标准 第 6 页（共 14 页） OUT Y006LD X004OUT S213LDN M0.0A M0.1= Q4.1 LDN M0.0= Q4.24。LD M0.0 AN I0.1= M0.3A T5= Q0.0AN M0.4= Q0.15.LD I0.3A C20ON I0.1A I0.2= Q2.1 LDN I0.1A C20可编程序控制器应用试题答案及评分标准 第 7 页（共 14 页） O I0.3AN I0.4= Q2.2五、计算题（共 14 分）1. 三菱电机 FX2-40MR 基本单元，其输入/输出点数为 24/16，用户程序为 1000 步基本指令，PLC 运行时不连接上位计算机等外设。I/O 扫描速度为 0.03ms/8 点，用户程序的扫描速度取 0.74s/步，自诊断所需时间设为 0.96ms，试计算一个扫描周期所需的时间为多少？1. 解：扫描 I/O 的时间：T1=0.03ms40/8 点=0.15ms扫描程序的时间：T2=0.74s1000 步=0.74ms自诊断的时间： T3=0.96ms通信的时间： T4=0扫描周期：T=T1+T2+T3+T4=（0.15+0.74+0.96）ms=1.85ms六、分析题1、某控制系统选用 CPU224，其中模拟量扩展模块以 2 字节递增的方式来分配地址。请按表中介绍的模块连接形式，填写模块 1 和模块 3 的地址分配。主机 CPU224模块 1 DI4/DO4DC24V模块 2 DI8DC24V模块 3 AI4/AO112 位模块 4 DI4/DO4DC24V模块 5AI4/AO112 位I0.0 Q0.0I0.1 Q0.1 I1.5 Q1.5I3.0I3.1I3.2I3.3I3.4I3.5I3.6I3.7Q3.0Q3.1Q3.2Q3.3Q3.4Q3.5Q3.6Q3.71.答案主机 CPU224模块 1 DI4/DO4DC24V模块 2 DI8DC24V模块 3 AI4/AO1模块 4 DO8DC24V模块 5AI4/AO1I0.0 Q0.0I0.1 Q0.1 I1.5 Q1.5I2.0 Q2.0I2.1 Q2.1I2.2 Q2.2I2.3 Q2.3I3.0I3.1I3.2I3.3I3.4I3.5I3.6I3.7AIW0 AQW0AIW2 AIW4 AIW6 Q3.0Q3.1Q3.2Q3.3Q3.4Q3.5Q3.6Q3.7AIW8 AQW2AIW10AIW12AIW142、某控制系统选用 CPU224，请按表中介绍的模块连接形式，填写模块 1、模块 3 和模块 4 的地址分配。可编程序控制器应用试题答案及评分标准 第 8 页（共 14 页） 主机CPU224模块 1 EM221 DI8DC24V模块 2 EM222 DO8DC24V模块 3 EM235 AI4/AO112 位模块 4 EM223 DI4/DO4DC24V模块 5EM235 AI4/AO112 位I0.0 Q0.0I0.1 Q0.1 I1.5 Q1.1Q2.0Q2.1Q2.2Q2.3Q2.4Q2.5Q2.6Q2.7AIW8 AQW2AIW10AIW12AIW142.答案主机 I/O 模块 1I/O 模块 2I/O 模块 3I/O 模块 4I/O 模块 5I/OI0.0 Q0.0I0.1 Q0.1 I1.5 Q1.1I2.0I2.1I2.2I2.3I2.4I2.5I2.6I2.7Q2.0Q2.1Q2.2Q2.3Q2.4Q2.5Q2.6Q2.7AIW0 AQW0AIW2AIW4AIW6I3.0 Q3.0I3.1 Q3.1I3.2 Q3.2I3.3 Q3.3AIW8 AQW2AIW10AIW12AIW14六、设计题1、一台三相异步电动机正反转控制的电路如下图（a）所示；PLC 控制的接线如图（b）所示。当按下正向启动按钮 SB1，电动机正转；当按下反向启动按钮 SB2，电动机反转；停机时按下停机按钮 SB3。过载是热继电器 FR 动作，电动机停止。按照上述工作要求：（1）分配 I/O通道；（2）选择 plc，画出梯形图。图（a）电动机正反转控制电路 图（b）PLC 控制接线图1、(1) 表 电动机正反转控制电路 IO 分配表可编程序控制器应用试题答案及评分标准 第 9 页（共 14 页） (2) 选西门子 S7-200 的 plc(也可以选其它型号 plc)图 电动机正反转控制电路的 PLC 控制程序2、两台电动机的关联控制：在某机械装置上装有两台电动机。当按下正向起动按钮 SB2，电动机一正转；当按下反向起动按钮 SB3，电动机一反转；只有当电动机一运行时，并按下起动按钮 SB4，电动机二才能运行，电动机二为单向运行；两台电动机有同一个按钮 SB1控制停止。按照上述工作要求：（1）分配 I/O 通道；（2）选择 plc，画出梯形图。2、 （1）关联控制功能的 I/O 分配表SB1 I0.0 总停按钮，常闭触点SB2 I0.1 电动机一正转起动按钮，常开触点SB3 I0.2 电动机一反转起动按钮，常开触点SB4 I0.3 电动机二起动按钮，常开触点KM1 Q2.1 电动机一正转运行KM2 Q2.2 电动机一反转运行KM3 Q2.3 电动机二运行（2）选西门子 S7-200 的 plc(也可以选其它型号 plc)可编程序控制器应用试题答案及评分标准 第 10 页（共 14 页） 图 电动机关联控制的 PLC 控制程序3、用接在输入端的光电开关 SB1 检测传送带上通过的产品，有产品通过时 SB1 为常开状态，如果在 10s 内没有产品通过，由输出电路发出报警信号，用外接的开关 SB2 解除报警信号。按照上述工作要求：（1）分配 I/O 通道；（2）选择 plc，画出梯形图；（3）写出对应的指令表程序。3、 （1）产品检测控制电路 I/O 分配表SB1 I0.0 光电开关，常开触点SB2 I0.1 解除报警开关，常闭触点Q0.0 报警信号T37 时间继电器（2）选西门子 S7-200 的 plc(也可以选其它型号 plc)图 产品报警检测的 PLC 控制程序4、下图是小车自动往返运动的主电路和继电器控制电路图。其中 KMl 和 KM2 分别是控制正转运行和反转运行的交流接触器。用 KMl 和 KM2的主触点改变进入电机的三相电源的相序，即可改变电动机的旋转方向。图中的 FR 是热继电器，在电动机过载时，它的常闭触点断开，使KMl 和 KM2 的线圈断电，电动机停转。工作时，按下右行起动按钮 SB2 或左行起动按钮 SB3 后，要求小车在左限位开关 SQ1 和右限位开关SQ2 之间不停的循环往返，直到按下停止按钮 SB1。按照上述工作要求：（1）分配 I/O 通道；（2）选择 plc，画出梯形图。可编程序控制器应用试题答案及评分标准 第 11 页（共 14 页） 图 小车自动往返运动的继电器控制电路图4、 （1）小车自动往返运动控制电路 I/O 分配表SB1 I0.2 停止按钮，常闭触点SB2 I0.0 右行起动按钮，常开触点SB3 I0.1 左行起动按钮，常开触点SQ1 I0.3 左限位开关，常开触点SQ2 I0.4 右限位开关，常开触点FR I0.5 热保护，常闭触点KM1 Q0.0 正转运行KM2 Q0.1 反转运行（2）选西门子 S7-200 的 plc(也可以选其它型号 plc)图 电动机正反转控制电路的 PLC 控制程序可编程序控制器应用试题答案及评分标准 第 12 页（共 14 页） 5、由两台三相交流电动机 M1、M 2组成的控制系统的工作工程为：当按下起动按钮 SB1电动机 M1起动工作；延时 5s 后，电动机 M2起动工作；当按下停止按钮 SB2，两台电动机同时停机；若电动机 M1过载，两台电动机同时停机；若电动机 M2过载，则电动机 M2停机而电动机 M1不停机。按照上述工作要求：（1）分配 I/O 通道；（2）选择 plc，画出梯形图。5、 （1）电动机控制的 I/O 分配表SB1 I0.0 起动按钮，常开触点SB2 I0.1 停机按钮，常闭触点FR1 I0.2 电动机 M1热保护，常闭触点FR2 I0.3 电动机 M2热保护，常闭触点KM1 Q2.1 电动机 M1运行KM2 Q2.2 电动机 M2运行T38 时间继电器（2）选西门子 S7-200 的 plc(也可以选其它型号 plc)可编程序控制器应用试题答案及评分标准 第 13 页（共 14 页） 请您删除一下内容，O(_)O 谢谢！ 2015 年中央电大期末复习考试小抄大全，电大期末考试必备小抄，电大考试必过小抄 Many people have the same mixed feelings when planning a trip during Golden Week. With heaps of time, the seven-day Chinese 请您删除一下内容，O(_)O 谢谢！National Day holiday could be the best occasion to enjoy a destination. However, it can also be the easiest way to ruin how you feel about a place and you may become more fatigued after the holiday, due to battling the large crowds. During peak season, a dream about a place can turn to nightmare without careful planning, especially if you travel with children and older people. As most Chinese people will take the holiday to visit domestic tourist destinations, crowds and busy traffic are inevitable at most places. Also to be expected are increasing transport and accommodation prices, with the possibility that there will be no rooms available. It is also common that you ll wait in the line for one hour to get a ticket, and another two hours at the site, to only see a tiny bit of the place due to the crowds. Last year, 428 million tourists traveled in China over the week-long holiday in October. Traveling during this period is a matter that needs thorough preparation. If you are short on time to plan the upcoming Golden Week it may not be a bad idea to avoid some of the most crowded places for now. There is always a place so fascinating that everyone yearns for. Arxan is a place like this. The beauty of Arxan is everlasting regardless of the changing of four seasons. Bestowed by nature, its spectacular seasonal landscape and mountains are just beyond word. Arxan is a crucial destination for the recommended travelling route, China Inner Mongolia Arxan Hailar Manzhouli. It is also the joint of the four prairies across the Sino-Mongolian border, where people gravitate towards the exotic atmosphere mixed with Chinese, Russian, and Mongolia elements. As a historic site for the Yitian Battle, Arxan still embodies the spirit of Genghis Khan. Walking into Arxan, you will be amazed by a kaleidoscope of gorgeous colors all the year round - the Spring azaleas blooming red in the snow, the Summer sea wavering blue in the breeze, the Autumn leaves painted in yellow covering volcanic traces, and the Winter woods shining white on the vast alpine snowscape. Hinggan League Arxan city is situated in the far eastern area of Inner Mongolia Autonomous Region. Its full name Haren Arxan means hot holy water in the Mongolian language. Arxan is a tourism city in the northern frontier with a blend of large forest, grand prairies, vast snowfield, heaven lake cluster, thermium, as well as volcanic cluster. It is a rare and unique ecotourism base filled with healthy sunshine, clean air and unspoiled green. Nestled close to the countrys largest virgin forest, and known for its spring and ecological environment, Arxan is marveled at by many tourists as the purest land on earth. You cannot miss out the Autumn of Arxan. It is definitely the best with brightly-colored scenery full of emotions. Autumn in the northern part of the country comes earlier than the South. A September rain followed by the footprints of Autumn brings more colors to the once emerald green mountain and blooming grassland. Shutterbugs flock to see for themselves the marvel of splendid colors around the mountains and waters, many of whom have travel a long distance and even camp here only to capture a moment of the nature wonder. The silver birch turns golden, while the larch is still proudly green. You will find yourself drowned in the intoxicating red of the wild fruits as well as the glamour of flowers in full blown. And your heart will be lingering on the woods as its time for the wild fruits to ripe. The picturesque Arxan in Autumn is indeed a fairyland only exists in a dream that satisfies all your fantasies. If it rains heavily on Saturday night, some elderly Chinese will say it is because Zhinu, or the Weaving Maid, is crying on the day she met her husband Niulang, or the Cowherd, on the Milky Way. Most Chinese remember being told this romantic tragedy when they were children on Qixi, or the Seventh Night Festival, which falls on the seventh day of the seventh lunar month, which is usually in early August. This year it falls on Saturday, August 2. Folklore Story As the story goes, once there was a cowherd, Niulang, who lived with his elder brother and sister-in-law. But she disliked and abused him, and the boy was forced to leave home with only an old cow for company. The cow, however, was a former god who had violated imperial rules and was sent to earth in bovine form. One day the cow led Niulang to a lake where fairies took a bath on earth. Among them was Zhinu, the most beautiful fairy and a skilled seamstress. The two fell in love at first sight and were soon married. They had a son and daughter and their happy life was held up as an example for hundreds of years in China. Yet in the eyes of the Jade Emperor, the Supreme Deity in Taoism, marriage between a mortal and fairy was strictly forbidden. He ordered the heaven troop to catch Zhinu back. Niulang grew desperate when he discovered Zhinu had been taken back to heaven. Driven by Niulangs misery, the cow told him to turn its hide into a pair of shoes after it died. The magic shoes whisked Niulang, who carried his two children in baskets strung from a shoulder pole, off on a chase after the empress. The pursuit enraged the empress, who took her hairpin and slashed it across the sky creating the Milky Way which separated husband from wife. But all was not lost as magpies, moved by their love and devotion, formed a bridge across the Milky Way to reunite the family. Even the Jade Emperor was touched, and allowed Niulang and Zhinu to meet once a year on the seventh night of the seventh month. This is how Qixi came to be. The festival can be traced back to the Han Dynasty (206 BC-AD 220). Traditionally, people would look up at the sky and find a bright star in the constellation Aquila as well as the star Vega, which are identified as Niulang and Zhinu. The two stars shine on opposite sides of the Milky Way. Customs In bygone days, Qixi was not only a special day for lovers, but also for girls. It is also known as the Begging for Skills Festival or Daughters Festival. In this day, girls will throw a sewing needle into a bowl full of water on the night of Qixi as a test of embroidery skills. If the needle floats on top of the water instead of sinking, it proves the girl is a skilled embroiders. Single women also pray for finding a good husband in the future. And the newly married women pray to become pregnant quickly. Tradition transformed The love story of Niulang and Zhinu, and the Qixi Festival have been handed down for generations. Yet these ancient traditions and customs are slowly dying out. Many modern Chinese, particularly youngsters, seem to know more about St Valentines Day on February 14, characterized by bouquets of roses, chocolates and romantic candlelight dinners, than they do about their home-grown day for lovers. Even Qixi is nowadays referred to as the Chinese Valentines Day. More and more young Chinese people begin to celebrate this day in a very similar way as that in western countries. Fewer people than ever will gaze at the heavens on Saturday to pick out the two stars shining bright on either side of the Milky Way, that is, if people even know on which day Qixi falls. There are ready reminders dotted about, in the form of big ads saying Sales on Chinese Valentines Day! in shops, hotels and restaurants. But few young women will mark the festival with their boyfriends, or take part in traditional activities to pray for cleverness. A large-scale of exhibition on the Silk Road opened to the public in the National Museum on Thursday. The exhibition displays more than 400 treasures from Shaanxi province, Gansu province and 14 other regions. It is largest scale exhibition that shows the history of the Silk Road in recent years. As APEC is going on in Beijing, the exhibit aims to show the world this brilliant section of history. The Silk Road is a series of trade and cultural transmission routes that were central to cultural interaction through regions of the Asian continent. It connected the West and East by linking traders, merchants, pilgrims, monks, soldiers, nomads, and urban dwellers from China and India to the Mediterranean Sea during various periods of time. I met my dear hubby in 2009 the second year I was in my school and it was the first year when he came here. We became colleagues. And there was nothing special happening during that year. He was just a kind and humble brother graduated from the same college as me. But we did not know each other till he became my colleague and his office desk was just in front of me. There was only a glass between us. So actually we could see each other when we both look up. But it is not the main reason that really draws us close. How we become close to each other was something seems quite natural. We went out to play badminton with other colleagues and we sometimes chatted for a while. He is a man of few words but somehow sometimes will say something really humorous. Then one day, to my great surprise, I found a pot of beautiful flower on my desk. It was just the flower I had talked about with my colleague the other day, and I thought it was her who put the flower there. But the truth is not. It was the humble guy sitting in front of me. He just simply said ,”well, I caught sight of this flower and thought that its beautiful and you may like it”. I wonder why I was moved because of these simple words and present. Maybe it is the sincerity and the true self that impress me. I thanked him and some colleagues walked past my desk would appreciate the beautiful flower and they noticed that something romance happened there. Then later on, there were some little surprises once in a while. Once, there was something wrong with my drawer and I had complained about it unconsciously. And he fixed it for me. Then the other day, he placed several pink diamond roses beside the flower with a piece of paper saying” I love you more than I can say! Diamond stands for marriage, rose stand for love. I hope you are mine, become my wife. You are the only girl who I really want to spend the rest of my life to stand by.” Although there were some grammar errors but I got what he meant. He meant so clear and so direct. And actually, I accepted him some days earlier. I was just waiting for him to break the ice. So finally, the common interests and the common understanding brought us together. Some people say the relationship and the feeling will change after getting hitched. You will find that love is no longer strong and there is always lack of passion and whats worse you may find out many bad habits of your partner, which never appear when you are first in love before the marriage. It seems that many faults turn up after you truly living together and see each others face the moment you open your eyes in the early morning. But after almost 4 years from now, I do not feel any negative change in our relationship. During all these years, we know each other better and we become more tolerant about each other and I realize that if you really love a person you will accept his imperfect. And what is the qualification of a good husband? Once I was chatting with my colleague about this issue. And one of the qualifications I thought was that he must be a good cook. But to my surprise, my colleague said