When the manager came in，the workers pretended________hard on their machines.
| A．to work | B．to be working |
| C．to have worked | D．working |
_________ we admit that there are still some problems about NMET, we don't mean that it is of no use.
| A．Until | B．While | C．As | D．Unless |
China and the United States held their first strategic dialogue on August 1 and _______ to increase co-operation and constructive relations.
| A．agreed | B．would agree | C．have agreed | D．had agreed |
It’s reported that a plane with five people _______ crashed into the mountain several days ago.
| A．on board | B．on the board | C．in board | D．in the board |
--Why are your group so happy?
--Our group _______ theirs in the oral English competition.
| A．has won | B．have gained | C．has beaten | D．have defeated |
______ to somebody, a British person often shakes hands with the stranger.
| A．Introducing | B．To introduce | C．To be introduced | D．On being introduced |