Every means ___ the river from being polluted.

She __________ to have lunch with her friend,saying that she wasn’t feeling well.

one thing to enjoy listening to good music, butit is _______ another to play it well yourself.

Did he write to you last week?-Yes，he ________ to me.What’s the matter with Bill?

This special school accepts all disabled students, _____ educational level and background.[ ]