Love is_____ makes you smile when you are tired.

A. that B. what C. it D. which

______ before bed, cellphones can result in a restless night.

A. To use B. Using C. Used D. Having used

________carefully if any change occurs when doing experiments in the lab.

A. Observe B. To observe

C. Observed D. Observing

Their relationship_______ ups and downs over the past century.

A. will see B. sees

C. has seen D. had seen

I have told you the truth. ______ I keep repeating it?

A. Must B. Can C. May D. Will

There is no greater pleasure than running on the playground, ____ after a ball.

A. chased B. chasing

C. to chase D. having chased

-- How was your trip to London ?

-- Great. I was helped by an organization. Otherwise, I _____ it.

A. wouldn’t afford B. hadn’t afforded

C. wouldn’t have afforded D. needn’t have afforded.

----Why did the general insist_______ a visit to the small village?

----It was at the very place______ he fought 30 years ago.

A. on paying, that B. to pay, in which

C. on paying, where D. to pay, which

We shall not start the project until it_____ by the committee.

A. will be approved B. has been approved

C. approves D. is to approve

Many people can’t learn lessons from the mistakes they’ve made_____they get hurt somehow.

A. whether B. unless C. if D. as