When you decline an invitation, you should always include ________.
A. time and place
B. a reason or an excuse
查看答案
Which is a polite way to decline invitation?
A. No, I can't.
B. I'd love to.
C. I'd love to, but I have to do my homework. Maybe next time?
Match the words with correct definitions.
一篇论文最重要的价值在于：
A. 是否发布
B. 发表在什么刊物上
C. 是否具有学术价值
D. 是否具有参阅性
以下不同粘度等级齿轮油,最能适应高温工作环境的是( )。
A. 80W
B. 85W
C. 90
D. 140
微信支付 
支付宝支付