You had better_________because you have to drive back home.

_________ is known to us all that the earth is smaller than the sun.

The city of Nanchong has grown so fast that it’s at least     what it used to be.

 _______ the smoke come out of the building, my first thought was to call the fire department as soon as possible. 

I can’t thank you _____ much for your kindness because without your help I wouldn’t have won the big prize in the speech contest.