29.Although going to school_________most of their time, students in the country always help the parents with the house-work.
Finding information in today's world is easy.The ________ is how you can tell if the information you get is useful or not.
Friendship is both ________ source of pleasure and ________ component of good health.
As ______ mountains surrounding our village are turning much greener, they have become ________ home to a large number of wild animals.
.—You've dropped ________ “s” in the word “acros”.—Oh, ________ letter “s” should be doubled like this “across”.
We Chinese have a dream— ________ dream to turn a welloff life into ______ reality by 2020.