---Where will you start your work after graduation? ---Mum, it’s not been decided yet. I____ continue my study for a higher degree.
——Hi, Mike.Any idea where Mary is? ——She ____ in the classroom.I saw her there just now.
—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, ______.