I.单项选择。（每小题1分，共15分）
( ) 1. It ______ sunny today, but it ______ cloudy yesterday.
A. is, is B. was, was C. is, was D. was, is
( ) 2.You should buy a T-shirt for ________.
A. you B. yourself C. my D. myself
( ) 3. -Where did you go on vacation?
-______. I could hear birds singing. It was really interesting.
A. I went to a movie B. I visited the museum
C. I learned to play the violin D. I went to the mountains
( )4.Tom arrived ______ Beijing on the afternoon July 28.
A. on B. to C. at D. in
