They have been skating __________.
| A．for three hours | B．since three hours ago |
| C．three hours ago | D．since three hours |
Hefor ten years.
| A．has been married | B．married | C．got married | D．has married |
Students should learn howproblems.
| A．solve | B．solving | C．can solve | D． to solve |
They arrivedShanghai a cold morning.
| A．in: in | B．in: on | C．at: on | D．at: in |
Who designed this game?
Itby Tom in 1999.
| A．is designed | B．designs | C．was designed | D．designed |
It is importantpeoplelearn team spirit.
| A．of; of | B．of; to | C．for, to | D．to; to |