--- It’s difficult for the village children to cross the river for school. --- I think a bridge ________ over the river.
The room was very dark, so I couldn’t see anything ______
--- Can you play tennis with us now? --- _____. I have to finish my homework first.
---I think everyone needs the sun. ---Yes, it can __ light and heat itself.
While she _____ TV, someone _______ at the door.
---Can you tell me __________? ---Yes. She came here on foot.