Trees used to be ______ for cooking by the villagers in the 1970s. A. cut up B. cut down C. cut off
________________ a book in the library, enter a key word into the computer.
Studying in groups is necessary _________________ you want to do well in school.
---Whose is the pencil box? ---It ____________ be Tom’s. Look at his name on the cover!
Could you record the football game for me? I can’t watch ____________ later.
Martha is a _______________ girl. She always smiles and says hello to others.