Zhang Guoli ________ the public ________ his son’smisbehavior.

use the telephone on the table, sir–Under no circumstances _________ to use the telephone in the office for personal affairs.

Why have they sent me this bill? I _____it several weeks ago[ ]

— I have got a headache. — No wonder. You ______ in front of that computer toolong.[ ]

ists have advanced many theories about why human beings cry tears, none of _________ has been proved.