Be careful . You _______ cross the road when the traffic light is red . The traffic is heavy at this time of day .

That bag is too ________, who can help me carry it?

Can we find before an earthquake?—-Yes. Some animals will run wildly and some plants will come out in the wrong season.

No matter how bright a talker you are, there are times when it’s better ______ silent.

_____, it was very difficult, but about an hour later it became easier.[ ]