_______ from father to son, the music has not changed for centuries.

 Taking this kind of medicine, if ________, will do harm to health.

—The hall___ for international conferences is of great importance—I see, and we are sure to complete it on time

The new schoolbags and books _____by some warmhearted people arrived at the village school the day before yesterday. 

______on his past mistakes, Ted realized that he had stayed around the wrong people.

Some very common things such as    to the sun for a long time will do harm to people's skin and even cause skin cancer

Tom asked the candy makers if they could make the chocolate easier       into small pieces.

 _____ what would happen，none of them could find a way out. 

With more forests _____being destroyed, huge _____ of good earth _____ washed away each year.

I suggested that the problem _____as soon as possible.

When ________ to the market, these products were very popular.

There are many talented actors out there just waiting _______.

Tom, look at your shirt! It requires ________. 

He feels it dangerous for a girl to be out late at night, so he won’t have his daughter _______ home late.

The students ________ from the whole class are expected to bring us honor in this school sport meeting.

When I entered the room I found my father _______ in the sofa and __________ in a magazine.

What upset the child most was _________to play games on the computer before he finished his task. 

He is afraid to face the difficulty he thinks he’ll have     the driving test tomorrow; he finds it difficult    rid of the worries．

It’s easier to catch a _____ lion than the one that’s awake. 

Mr. Smith didn’t go to the party because he had a lot of experiments _____.