Now let me tell you the work I have been doing with them. My job with the UN is not paid, but voluntary and as I said _______, I mainly visit countries where the UN has programs to help people.
All the elder people ______ at the party were those _____involved in (参与)community service.
In the past, ice used to ______ used to ______ the air in a room.
The old man’s _______ pity on the snake led to his own death.
________ many times, but he still could not understand it.
Faced with a bill for $ 10,000,_________.