The country has _____ several wars in the past century and people there are still living a poor life.

Please _________ the light when you leave the classroom.

Please say something about Zheng He. —Oh! He is the Ming dynasty explorer of ______ all the Chinese are proud.

disaster occurs, all people, ________ they are old or young, rich orpoor, try their best to help those in need.

Do you know _____—Sorry, I don’t know.