—Flight 331 _____．I'd better be on my way．Goodbye．
—Bye．Happy landing!
| A．is announced | B．is being announced |
| C．is announcing | D．has announced |
Not recognizing me at first, __________.
| A．he closed the door | B．the door was closed |
| C．the door was close | D．I closed the door |
She was always _____ , even when things were at their worst.
| A．attractive | B．optimistic | C．pessimistic | D．frightened |
This also keeps the air，soil，water crops________ chemicals.
| A．out of | B．out from | C．free of | D．rid of |
____polite to others and you can get friendship in turn.
| A．Be | B．To be | C．Being | D．/ |
There are many tall old trees____ in and around our school.
| A．stood | B．to stand | C．standing | D．being standing |