Mr． Black walked around and offered help____we were doing an experiment．（ ）
| A． |
while |
B． |
although |
C． |
until |
D． |
unless. |
Do you know _____next Friday，Lily？
| A． |
If it doesn't rain，we will． |
| A． |
if we will take a field trip |
| B． |
will we take a field trip |
| C． |
why we will take a field trip |
Look out!Something____ down from the building．
Dear me!It's too dangerous．（ ）
| A． |
fell |
B． |
falls |
C． |
is falling |
Murray plans to study art in the U．K．His friends will____off at the airport next week．（ ）
| A． |
take |
B． |
see |
C． |
leave |
I can hardly see the words on the screen．
Well，let's go and take the front seats so that we may see_____（ ）
| A． |
clear |
| B． |
clearer |
| C． |
more clearly |
I didn't hear you come in just now．
That's good．I tried ______the baby up（ ）
| A． |
to wake |
| B． |
not to wake |
| C． |
waking |