孙楠同学用如图所示的电路研究导体中的电流跟导体电阻的关系,他先后将5Ω、15Ω和25Ω的定值电阻接入电路A、B两点间,闭

1.This math problem is too difficult for me to work out
2.SunNan is a professional singer.
3.WangNan began to play table tennis when she was a little child.

Dear Wang Ning
I'm glad that we can go shopping together.There are three popular stores in our town.
The first one is called Hua Li Store,which is famous for its high-quality clothes.With its luxuray brands and best service,the store attracts some fashion pursuers and people who treasure good quality.The RedStar Supermarket is the biggest but the cheapest one in the town,so there are many shoppers visiting around.The third one I will introduce to you is People's Store,the most popular place in the town,where I strongly recommend you to spend more time.It locates in the subway station,the goods there is not very cheap or expensive,which is considered to be able to meet the majority's needs.
Regards
Yours Sun Nan

B

将来我将会成为像孙楠那样的歌手
In the future I will be a singer like sun nan

正如楼上所说,孙楠唱得没错.
不见不散：Be there or be square.
A 'square' is a person who is ordinary or conservative in behavior or demeanor,not 'cool' or 'in.' The writer is saying that if you are not part of the scene or the action,then you are not cool.I think this is relatively new in usage,but I am unsure of the origin.
Immediately after World War II the word "square," which had long meant honest,direct,solid,became the antonym of hip or hep or sphisticated,at least in the U.S.A.Someone who didn't like or pretend to understand jazz and swing was "square." The word came to have a somewhat broadened use as out of touch,conventional,old-fashioned,not "with it." The latter expression is as dated as "Be there or be square."