Development of science and technology must benefit people ______ harm them.     

It was impolite of him ____without ____good－bye

--- Why were you so late for work today？

--- ________ to the office was very slow this morning because of the traffic.

Only after you finish your homework ______TV.

______the room, a letter was seen lying on the desk.

I’m afraid I am not fit for the job, for it is ______calling for much patience.

Our football team _____ every match so far this year, but we still have three more games to play.

Using Dr Yuang's hybrid rice, nowadays farmers are producing harvests ________ before.

Smiles around the world _____ be false, ______ other feelings like anger, fear or worry.

The specialist, ______ some of his assistants, ____ to attend our discussion.