he explained ,         we understood .

 An ________ boy came to our class yesterday.

---What’s the low-carbon(碳) life style like?----Save        energy, produce            carbon. 

－ Take one more pen. If your pen doesn’t work during the exam, you can use the other one.－ OK, Mum. You are always_______.

---- If you want to have a hot bath, you should pay ________ money.---- You mean the fee of hot baths is not ________ in the hotel price?