电针法

Try reading the following sentences as fast as you can. “She sells seashells by the seashore. The shells she sells are surely seashells. So if she sells shells on the seashore, I’m sure she sells seashore shells.”

Not very easy, was it? What you’ve just read is called a tongue twister (绕口令). It is an exercise made up of sounds that are hard to pronounce(发音，读) in order to help people pronounce words faster and more correctly. Try the next example.

“Peter Piper picked a peck of pickled pepper. Did Peter Piper pick a peck of pickled peppers? If Pete Piper picked a peck of pickled peppers, where’s the peck of pickled peppers Peter Piper picked?”

Tongue twisters usually do not have much meaning. They are just designed to improve people’s ability  to pronounce words. Although they may be very difficult, these exercises are very important to people who are trying to speak English correctly. This is because tongue twisters help people to tell the differences between similar sounds.

So if you wish to pronounce words more smoothly, you’d better try picking out some tongue twisters and practicing them.

小题1:Tongue twisters are helpful in improving ___________ skills.

A．listening

B．writing

C．pronunciation

D．communication小题2:The first tongue twister is hard because ___________.

A．it is very boring to read

B．it teaches us a lot of knowledge

C．we don’t know who “she” is

D．the sounds of “s” and “sh” are similar小题3:The passage is probably taken from _________ in a school newspaper.

A．Story Time

B．Study Garden

C．Latest News

D．Lost and Found

物体甲的位移s与时间t图象如图甲所示，物体乙的速度v与时间t图象如图乙所示，则下列判断正确的是（　　）

A．0～6s内，甲运动方向一直不变

B．0～6s内，乙运动方向一直不变

C．0～6s内，甲的位移大小为4m

D．0～6s内，乙的位移大小为4m

在一般的废水处理过程中，除磷脱氮主要在( )中完成。

A．一级处理

B．二级处理

C．三级处理

D．四级处理

意外伤害附加保险因意外伤害导致死亡的一次性补助为多少元？（）

A.40000元。

B.60000元。

C.50000元。

艾士卡法测定全硫时，只有当含硫量大于2%时，才需要在计算时减去空白值。