It's not necessary to explain the truth________there are air,water and sunlight,there are living things.
It is beyond my understanding that many adults ______ be so crazy about Harry Potter series.
---What bad luck! I had a cut in salary yesterday. --- _____. I warned you not to be late repeatedly but you ignored it.
Hey, look at your pale face; you must have stayed up late last night, _____?
Hurry up! We need to get to the top of the mountain before the sun ____ in thewest.
The hard part in our life is not making the decision but living with .