We work together to achieve our common purpose: __________ world that is safer, cleaner and healthier than __________ one we are living in.

________that China has the largest number of iphone4s users now.— I believe so.

Don’t worry, Sir. I’m sure I can run _________ to catch up with them.

I have seen the film Where Are We Going, Dad?.—__________. I think it’s wonderful.

It’s helpful_____ you to give me _____ useful advice.[ ]