Before the first nonstop flight made in 1949,it______necessary for all planes to land for refueling.
The classroom wants __________.
I’m going shopping. Do you have anything ________ ?
As he _______ , he was surprised to see that the man had disappeared.
He __________ his post because he had been offered a better job.
I’m not used to the way you speak to me. __________, I don’t want to continue the conversation.