Scientists _______ a lot of experiments on animals, hoping to find and effective way to cure the patients who had AIDS.

Putting in a new window will ______ cutting away part of the roof.

I always _____ on life when listening to Beethoven’s symphony.

Our parents and teachers often ________ the importance of study hard _______ us.

Sitting alone by the window, all the memories __________ .

The other day, when I was wandering in the street I ________ one of my old friend, Jim.

Driving on the road, drivers do ______ the traffic rules, which is responsible for themselvesas well as others.

As we all know, a man's worth cannot be ______ by his looks.

—Li Feng won the first prize in the national English competition.—Oh，really？I’m glad that her efforts at last________.

Who do you think is the right person to ______the task?

Without proper lessons, you could ___ a lot of bad habits when playing the piano.

I want to ________ a question to the chairman but in a moment I lost my nerve.

Do you know the stages every inventor must ________ before they can have their invention________ .

His winning the competition has ___ his confidence of himself.

Being in the hospital for six months, he felt as if he was ____ from the outside world.

— Have you       ?— No. I had the wrong number.

Many memories of old times were        by the conversation we had together that evening.

When argument ________ in a relationship between two people, a usual way of dealing with this is to send messages through a third person.

With the environment worsening, the government ______ people for more environment protection．

The party was meant to be a surprise to everyone who would take part, but one of the organizers _______ the plan．