21. As _______ unemployment is very high at the moment, it's very difficult for people to find________ work.
A.the, 不填 B.不填，不填 C. the, a D. an, the
22.—Who is making so much noise in the garden?
—_________ the children.
A.It is B. They are C. That is D. There are
23. Yesterday I was walking downstairs when I missed my foot and had a bad fall, nothing serious __________
A. even B. either C. then D. though
