__ carefully if any change occurs when doing experiments in the lab..
#88398
A
Observe
B
To observe
C
Observed
D
Observing
推荐题目
Tsinghua University, _____in 1911, is home to a great number of outstanding figures.
#90214
A
found
B
founding
C
founded
D
tobefounded
We hope your suggestion will contribute __________ the problem.
#88240
A
to solving
B
to solve
C
of solving
D
solved
--- It seems that the manager is very unhappy. --- Surely she is. You see, Steve left the company half an hour ago, with his work_______.
#97038
A
to leave unfinished
B
was left finishing
C
leaving to finish
D
left unfinished
We finished the run in less than half the time _________．
#97914
A
allowing
B
to allow
C
allowed
D
allows
Last night, there were millions of people _______ the opening ceremony live on TV.
#88397
A
watch
B
to watch
C
watched
D
watching