_____ riding your bike to the park —Good idea.

A study suggests reducing energy demand in the future may _______ urban areas.—That’s true. Cities need more energy than small towns or other rural areas.

w library, ______ last week, isvery popular _____ the students

下列各句中词语使用正确的一项是（ ）

ering his health, I advisehim to ______ an hour or two each day to work out