The case of his death is being ________ and will be found out before long.

The book didn't ________ children probably because it employed too many scientific terms.

The computer system suddenly________ while he was searching for information on the Internet. 

Dogs are clever animals and they can be trained to ________ houses.

—Thanks a lot, Mr. Wang. I don't know how to ________ the help you gave me during my stay here.
—It's my pleasure. Welcome to China again when you have time.

Tom's secondhand car wasn't in use and for that reason he ________ it in the newspaper.

In the time of social reform, people's state of mind tends to  ________with the rapid changes
of society.

We are still dealing with problems ________ errors made in the past.

The little girl ________ dreaming a sweet dream.

If we ________ the waste materials,a lot of money will be saved.