This _____ my brother. ______ is my friend.
---Dad,I’m afraid I can’t do well in tomorrow’s English test.--- ___________.You ’ve been working hard these days.I believe you can do it well.
--- I feel nervous about the coming summer.---- Me , too. Hot weather _____ makes people feel hot, ______ causes serious health problems.
--- What do you think of the math problem ?--- It’s very hard and nobody has _______.
—Come and join us, Jimmy!---I’m sorry, but I’m really busy now. If I ________ time, I would certainly go.
The environment is becoming worse and worse. I think we should do something to ____ people ____ cutting the trees in order to protect the earth.