Years ago we didn’t know this, but recent science _______ that people who don’t sleep well soon get ill.
—Have you thought of the topic for the composition? — Not yet.I _____ it very carefully, but I haven’t decided.
The most important thing about cotton in history is _____ part that it played in ____ Industrial Revolution.
People have planted a lot of trees and grass in order to ____ wind and sand in the desert.
Read the passage and correct the mistakes, ______.
—What do you think of the concert given by the famous Hong Kong singer? —Not so good.In fact, it _____ to be a great disappointment.