----Have you any letters _______, sir?---No, thanks. You may take a rest.

Advertising is different from other forms of communication in that the advertiser pays for the message         .

—Where are you ________? —I’m going to the airport to ________ my friend.

After walking on the zigzag path to the mountain top for a few hours, the tourists gathered under trees_____ shade and______ down to have a rest.

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