(2013·安徽卷)It be the vocabulary that caused you the problem in the exercise because you know a lot of words.
It is dangerous to __________ in the forest,because you are easily lost.
The dictionary __________ 10,000 words,__________ many in science.
The policeman stopped the stranger and asked him where he __________.
_________ you are right in refusing to join that club.
Life is like a long race __________ we compete with others to go beyond ourselves.