下列选项中哪一句话中的动词sing(唱歌)可以作为主句的谓语？ A: I know a man who sings well. B: Singing well, the man receives wide acclaim. C: He is singing.He is singing. D: Singing is so hard.

( )9. He asked _______ outside . A: A. who are singing B: B. who was singing C: C. who singing was D: D. who is singing

. He teaches singing at a high school and is acknowledged to be ______ singer as he is a teacher.

He prefers ___ to ___. A: singing; dancing B: sing; dance C: to sing; dance D: singing; dance

Which sentence problem is involved in “The subject was trained as a singer, but he could not make a living by singing, and he had to find another way to make money, so he gave up singing as a career.”?

—Is the man who is singing your teacher? —Yes，he teaches ______ Physics.

My childhood dream is to be a vocalist like Pavarotti. In my eyes, he regards singing as a _____ ( 天职 ).

He was often heard ( ) in the next room. A: sing B: sung C: to sing D: singing

He _______ when the teacher came in. A: A.sang B: B.has sung C: C.was singing

Who is singing? Oh, ____________ Xiao Liu. A: it's B: he's C: this is D: she's