In debating, one must correct the (opponent's) facts, deny the relevance of his proof, or deny (that) (what) he presents as proof, (unless) relevant, is sufficient.

A:opponent''s B:that C:what D:unless

(Because) of the recent accidents, our parents forbid my brother and me (from swimming) in the river (unless) someone agrees (to watch) over us.

A:Because B:rom swimming C:unless D:to watch

You (will not able) to pass the examination (unless) you work (harder) than you (do) now.（　）

A:will not able B:unless C:harder D:do

The water will be further polluted unless some measures （）.

A:will be taken   B:are taken     C:were taken     D:had been taken

The water will be further polluted unless some measures ______.

A:will be taken B:are taken C:were taken D:had been taken

The water will be further polluted unless some measures ______.

A:will be taken B:are taken C:were taken D:had been taken

The children are required not to leave the building unless（）to do so

A:being told  B:they will be told   C:be told D:told