I took the wrong train _______. I didn’t even know it until half an hour later .

Is your mother very strict ____ her work – Yes, she is strict ____ me, too.

A teacher’s________to the cause of education is worth great respect of the whole society because it brings countless benefits to the development of society.

Not until he arrived home _____ he find that this wallet had been stolen.[ ]

The wide spread of super hybrid rice aroundthe world ______ the lives of millions and millions of people suffering fromhunger to a great level.