We are now short fresh water. Something must be done to prevent people polluting it.A. of;from B. for;from C. of;to
--Are there ______ books in the box?--Yes, there are ______.
--What are your ?-- They are workers.
Some students have eggs and apples ______ breakfast.
-- ______ today?--It’s Monday.
There are ______ boys on the playground.