He is never allowed ________ in the room.
I found the homework was not so heavy as __________ I __________ to get in my old school.
—May I ask a question after class, Sir? — __________, but not during my lunch break.
Many people have fully realized it's important to keep __________ balance of __________ nature. Otherwise, humans will be punished by it.
He lost his __________ and fell off his bicycle.
—Do you need any help, Lucy? —Yes. The job is __________ I could do myself.