Many people ________ the car accident, so it was not difficult to investigate．

A．witnessed

B．urged

C．swallowed

D．drugged

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

A．arrive

B．arrived

C．to arrive

D．arriving

________ the rooms, we began to weed the garden．

A．Cleaning

B．Having cleaned

C．Cleaned

D．Having been cleaned

It's unnatural for a mother to leave her child ________ to enjoy herself．

A．alone

B．lonely

C．lone

D．loneliness

We must learn to ________ the new life when going abroad．

A．adapt

B．adapt to

C．adapt with

D．adapt in

It is said that walking is one of the best ways for a person to ________ healthy．

A．reserve

B．preserve

C．stay

D．obtain

We hope the bridge ________ the road ________ will be completed as soon as possible．We can't bear the inconvenience any more．

A．of; carried out

B．to; being carried out

C．on; to be carried out

D．to; carrying out

According to the rules of the factory, you can ask for leave ________ you have a doctor's diagnosed note．

A．now that

B．on condition that

C．unless

D．even though

Bob is in a hopeless situation, ________ we will keep a very close eye on．

A．which

B．where

C．that

D．when

The life of a high school student is usually active, exciting and full of fun, but it ________ be stressful sometimes．

A．must

B．can

C．need

D．should