—I’m going to Thailand this summer holiday.
—
| A．Take care! | B．Write to me. |
| C．Have a nice trip! | D．When will you come back? |
.The cars _______ in Beijing are as good as those _______ in Shanghai.
| A．produce, produce | B．produced, produced |
| C．produced, producing | D．producing, producing |
The graduating students are busy _______ material for their reports.
| A．collect | B．to collect | C．collected | D．collecting |
I had to shout to make myself _______ above the noise.
| A．heard | B．hearing | C．heard | D．to hear |
.He walked down the hills, _______ softly to himself.
| A．sing | B．singing | C．sung | D．to sing |
.At this moment the bell rang _______ the end of class.
| A．announce | B．announcing | C．announced | D．to announce |