While I was in the Disneyland，I saw some children________in the roller coaster，laughing happily．
| A．sit |
| B．sat |
| C．to sit |
| D．sitting |
-Shelly, it’s cold today!_______put on more clothes?
-Ok.
| A．Why don’t | B．Why not |
| C．Would you mind | D．Would you like |
It is said there are ______ of people in the city of Wenzhou.
| A．nine million | B．millions |
| C．a million | D．million |
Tu Youyou is famous ____ her medical research and won the Nobel Prize this year.
| A．of | B．for | C．as | D．to |
-Is everyone here today? -No, Jack is at home____ he is ill.
| A．but | B．and | C．so | D．because |
You should take____ umbrella if it rains.
| A．a | B．an | C．the | D．/ |