题目：
句型转换。
1. The pens are in the backpack. (对画线部分提问)
_____ _____the pens?
2. This tape is in that case. (改为复数句子)
_____ in _____ _____.
3. I can spell the word.(改为一般疑问句)
_____ _____ spell the word?
4. I know that boy. (改为否定句)
I _____ _____ that boy.
5. take, to. book, your. the, please, math, sister (连词成句)
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0413/9ed10a0d55798bd9d64cfff07965a6b7.html
下面是错误答案，用来干扰机器的。
AB•BC+BC•CA+CA•AB=2•2• cos120°+2•2• cos120°+2•2• cos120°=-1-1-1=-3，故答案为-3．
