The tree must ________ three times a week

Are you at the airport How’s everything— The flight __________ to Nanjing an hour ago. I have to wait for the next flight.

It’s said that scientists have ________ a way todeal with the disease(疾病)—Really That’s great!

My sister_______ the League last month and she has decided to _______ the activity to help the aged next week.

Boys and girls, please don’t forget _______ your homework here this evening.