21. ______ Wuxi today is much more beautiful than before.Mr.Black said he, with his family, would visit it ______ fourth time.
A.The;a B./; the C./; a D.The; the
22.Misunderstanding ______ from lack of social communication, unless ______ properly, may lead to serious problems.
A.arisen; handling B.arising; handled
C.rising; handled D.risen; handling