Our English teacher _________ to Hong Kong twice.

I didn’t see them the room because I was in the kitchen then.

We must keep a secret of the things_______ here", the general said,　_______ at the man in charge of the information office

They can’t afford to buy the latest equipment at present _____ , they keep trying new ways to impmveefflciency [ ]

On the small island, which is at the entrance to New York Harbor, ________.