A：Hello，this is Jack speaking in Beijing．May I （76） ？
B：Hey，this is Amy．（77） ？
A：I am visiting my aunt．I am calling to say good luck to you about your graduation exam．
B：（78） ．Have you ever been to Badaling？
A：（79） ．I went there yesterday．
B：（80） ？
A：I will be back in 6days．
B：See you then．
A：OK，see you!
We should be f to each other because we are brothers and sisters．
Throwing the litter h and there is a bad habit．
One t can′t make a forest， so we need teamwork．
Most Chinese think the color r is the symbol of good luck．
To live a low﹣carbon（低碳） life， we should t off the lights when we leave the room．