精选优质文档-倾情为你奉上 一、单项选择 1.He likes to watch his son the piano.A. playsB. to playC. playD. played 2.When I passed the classroom, I heard a girl in it.A. singB. losingC. sangD. singing 3.I saw them volleyball this time yesterday.A. playB. playedC. to playD. playing 4.When I walked past the park, I saw some old people Chinese Taiji.A. doB. didC. doingD. are doing 5.Do you hear the boy