21.We are sparing no efforts to create _____ more peaceful and more advanced world, ______ place where everyone enjoys his life and freedom.
A. the; a B. /; the C. a; a D. the; the
22. Housing price in China is so expensive that it is_______ the reach of those with average income, so the government is taking measures to solve the problem.
A. over B. within C. beyond D. below
23. Not until they left school ______ how much their teachers loved them and helped them.
A. they realized B. did they realize
C. they would realize D. had they realized
