—Li Ping, your cousin speaks fluent English, like a native speaker.
—No wonder. He once _____ in New York for two years as a visiting professor.
| A．had worked | B．has worked | C．worked | D．has been working |
This book is worth ______ .
A to read B．reads C．read D．reading
You should apologize ____ your teacher ______ being late again.
| A．to; for | B．for; to | C．/; for | D．to; to |
When _______ this question, she keeps silent.
| A．asked | B．asking | C．to ask | D．being asked |
Why _____ join us in the game!
| A．not to | B．don’t | C．not to | D．not |
____a living, she had to work from morning till night.
| A．To make | B．made | C．Making | D．To have made |