To make the air clean,Beijing will close some companies________cause heavy pollution.A.thatB.whoC.what
---_____ have you studied English? --- Since I was six.
— Kate! Let’s go to work right now. We’ll be late. — _____. We still have 20 minutes left.
She is often seen ______ the old woman.
_____ this way, you can work out the math problem.
All the information _____ writing the report.