---Be careful, don’t forget to follow your father.---I know that, Mum. One can never be too careful.
-Don’t stay up late, Dale! It’s bad for your health. -______.
I know nothing about American history. So when I ______ about it, I couldn’t answer it at all.
Our school is not very big. There are only about ______students.
-______ is it from your home to school? -It’s about ten minutes’ bus ride.
Look out! You ______ now. Please don’t talk on the phone.