Air, ________ we breathe every day, is around us all the time.

1. A.
   that
2. B.
   which
3. C.
   from which
4. D.
   from that

Air, _   __we breathe every day, is around us all the time.

A. that               B./            C. which                        D. it

Air, ______ we breathe every day, is around us all the time.
A that B / C which D it

Air, ________ we breathe every day, is around us all the time.

[    ] 　　

A. that   B. /   C. which   D. it

Air, ________ we breathe every day, is around us all the time.

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