当经介绍后认识某人，你应该说：
| A．Good morning |
| B．Please sit down. |
| C．Thank you. |
| D．Nice to meet you. |
, people shouldn’t drive so much.
A. To save water B. To save trees C. To save energy
When is World Environment Day?
It’s ___________.
A.on 10th September B.on 5th June C.on 22nd April
Look, Sam is starting a poster.
A.makes B.to make C.make
Plastic bagsthe park messy and dirty.
A. make B. makes C.making
To keep the air clean,don’tto work every day.
A. walk B. ride C. drive