You must have waited here for a long time ,___________you?
| A．mustn’t | B．didn’t | C．haven’t | D．hadn’t |
Neither Tom nor Jack and I ____ his students.
| A．are | B．am | C．is | D．was |
The rich ____ not always happy.
| A．are | B．is | C．has | D．have |
I, who____ your friend, will try my best to help you with your English.
| A．am | B．is | C．are | D．be |
The United States of America _____one of the most developed countries in the world.
| A．is | B．are | C．was | D．were |
The whole class _____the teacher attentively.
| A．are listening to | B．is listening to | C．are listening | D．is listening |