单项选择题：在三相交流系统中可能发生的短路故障出现最大短路电流的有( )。 A．三相短路 B

题型：单项选择题

How to Be Polite at a Dinner Party?

It’s not polite to arrive at a dinner more than 15 to 20 minutes late. The host or hostess usually waits for all the 21 to arrive before serving the meal. If someone is late，the food may be spoiled(变味)，and 22 may the host or hostess’ spirits．If you have to be 23 ， call and tell them to start 24 you．

It’s even worse to be early! The host or hostess will probably not be 25 ．If you are early，drive or walk around the block a few times，or just sit in your car until the right time．

Though it’s often 26 to arrive at a party on time，on the other hand，the host or hostess 27 guests to arrive and leave between certain times，so you can 28 at any time between the times he or she gives you．

It’s nice to bring an empty stomach，but it’s even nicer to bring 29 present．The present should not cost a lot，or you might make the host or hostess 30 ．Flowers，wine，or a box of candy will be fine． 31 bring money as a present．In an introduction，the 32 of a name is：(1)the given name；(2)the family name．In other 33 ，the given name comes 34 . It’s important not only to learn and remember 35 ，but to repeat them often in conversation．After the introduction，we usually call friends by their 36 names．Older people may want you to call them by their titles and family names，such as “Mrs. Smith”，“Mr. Johnosn”，“Dr .Brown”.

A maiden(闺女)name is a 37 family name at birth. In the United States and Canada，after a woman 38 ，she takes the family name of her 39 in place of her maiden name．It is now becoming common，however，for women to 40 their maiden names after they get married,

小题1:.

A．guests

B．visitors

C．customs

D．passengers小题2:.

A．or

B．so

C．but

D．yet小题3:.

A．tired

B． hungry

C．1ate

D．early小题4:.

A．without

B．for

C．with

D．after小题5:.

A．awake

B．ready

C．up

D．friendly小题6:.

A．useless

B．impossible

C．unable

D．important小题7:．

A．forces

B．invites

C．begs

D．orders小题8:.

A．play

B．fly

C．arrive

D．start小题9:.

A．a big

B．a small

C．a good

D．an expensive小题10:.

A．pleased

B．satisfied

C．interested

D．uneasy小题11:.

A．Never

B．Always

C．Do

D．Be sure to小题12:.

A．spelling

B．calling

C．order

D． pronunciation小题13:.

A．words

B．1etters

C．idioms

D．sentences小题14:.

A．1ast

B．first

C．finally

D．in the middle小题15:.

A．expressions

B．appearances

C．names

D．addresses小题16:.

A．given

B．family

C．middle

D．pen小题17:.

A．gentleman’s

B．boy’s

C．woman’s

D．man’s小题18:.

A．works

B．marries

C．bears

D．dies小题19:.

A．husband

B．mother

C．father

D．sister小题20:.

A． stop

B．give up

C．keep

D．find

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在三相交流系统中可能发生的短路故障出现最大短路电流的有( )。 A．三相短路 B

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