---Your grandfather still seems very energetic, although he is already in his seventies now.
---Yes, he _______in the army for three years when he was young.
| A．would serve | B．served |
| C．had served | D．has served |
Most of the world’s rice is grown in the tropical _______.
| A．section | B．location | C．district | D．zone |
Mary was so touched by Tom’s generosity that for a moment she was _______ for words.
| A．in loss | B．in a loss | C．at loss | D．at a loss |
Children must _______ road safety before they are allowed to ride a bike on the road.
| A．instruct in | B．instruct | C．be instructed in | D．be instructed |
The officer demanded that such things ________ from happening again.
| A．prevented | B．prevent | C．be prevented | D．were prevented |
After much _______, the shop owner agreed to cut down the price by 15%.
| A．debating | B．talking | C．discussing | D．bargaining |