Betty　　　eats junk food,so you see,she is pretty healthy. 

I can't see the words           .  on the blackboard. Please turn on the light.

The teacher can _________believe that Tom studies so ________.

My grandma started using Weibo at the age of 70. She always says it’s never ____ old to start doing things.

— Have you ________ watched the dolphin show in the Ocean Park in Hong Kong?—Not _________.