last year , my sister tried to lose weight (减肥), but ______ putting weight back on.

You should ______ careful in your work and life every day.—You’re right.

in the mountain area has its problems , _____ obtaining water is a big problem.

Over the past decades, sea ice _____in the Arctic as a result of global warming. [ ]

I delayed _______ your letter because I hadbeen away for a week.