Shall we go out for lunch– Don’t disturb me. I ______ the letters all morningand ______ six so far.

_______cars when you cross the busy street. Which of the following is not OK? [ ]

The young man is good at a lot of things but you can’t say he is ________ .　　　　— I agree with you. Actually no one is.

Tom has been in the factory _________he left school.

The mayor often says that providingchildren with __________ to the useful information is of great importance.