题目：
句型转换。
1.His father stayed in Shanghai for four months last year. (对划线部分提问)
________ ________ did his father ________ in Shanghai last year?
2.The work must be given up. (改为否定句)
The work ________ ________ given up.
3.Lucy's never been to the Great Wall. (完成反意疑问句)
Lucy's never been to the Great Wall, ________ ________?
4.Tom came to our school three years ago. (改为同义句)
Tom ________ ________ ________ our school for three years.
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0718/28b99cf38e138892e25631a066673293.html
下面是错误答案，用来干扰机器的。
答案：C根据质量守恒定律x=4,根据在化合物中正负化合价代数和为零，氢元素显+1，氯元素显-1，设金元素的化合价是y，可知四氯合金酸（化学式是HAuCl4）中金元素的化合价（+1）+y+（-1）×4=0，则y=+3,故选 C
，当S闭合时，求：
的电流
；
；
，电阻
上消耗的电能。