( )21. 26个字母中的元音字母是 。
A、A；I；O；U；Y B、A；E；K；U；Y
C、A；E；I；O；U D、A；D；O；R；U
( )22. ---- __________, are you Michael?
---- Yes, I am.
A. How old are you B. Excuse me
C. Thank you D. How are you
( )23. ---- Welcome to Canada.
---- __________.
A. Thank you B. Thank C. Thanks you D. Nice to meet you
