Your bedroom is very tidy and clean．
Thank you!It an hour ago．（ ）
| A． |
cleaned |
B． |
will clan |
| C． |
is cleaned |
D． |
was cleaned |
Doctor Bethune sometimes had to treat the wounded on _____ own．（ ）
A．himB．hisC．themD．their
The Three Gorges Dam produces _____for millions of people in China．（ ）
A．electricityB．influence
C．transportD．technology
Students here often do physics experiments _____small groups．（ ）
A．byB．inC．forD．at
To prepare for _____trip to LA， Betty is making _____list of things to take along．（ ）
A．the； theB．不填； aC．the； aD．a； 不填
There is so much noise in the next room．I wonder__________________．（ ）
A．what are they doingB．what were they doing
C．what they are doingD．what they were doing