重点句型解析
1. The string was getting charged! 细线正在导电。
get在这里是代替助动词be, 与过去分词连用，以强调主语的被动行为。
e. g. They got caught in the big rain on their way here.他们来这儿的路上遇到了这场大雨。
He got burnt while putting out the fire. 在灭火时他被烧伤了。
The car got stuck in the snow. 汽车陷在了雪中。
注意: get done有时不表示被动意思
e. g. Do you know she’s got married? 你知道她已经结婚了吗？
I’ve got used to such a way of life. 我已习惯了这样的生活方式。
get还有其他用法
(1)get用作使役动词时，其宾语补足语可用多种形式，用动词的什么形式取决于该动词与宾语之间的关系。get sth. / sb. to do/ doing/ done/ adj.
e. g. You must get them to come over here at once. ( = have them come)
你得想法让他们马上到这儿来。
I’ll get Mary to do the washing for you. (= have Mary do)我来让玛丽替你洗这些衣服。
Why don’t you get your shoes mended. (= have your shoes mended)你怎么不请人把鞋补一补。
I’ll go and get my hair cut. (= have my hair cut)我要去理发。
The next thing is to get the problem settled as soon as possible.
接下来就是尽快使问题得到解决。
(2) get to do表示从没有到有的变化，指不定式动词的动作或状态的开始，这时不定式动词大多为意识性或情感性的动词，动词come可代替get, 不改变这一作用。
e. g. I got to know him in 1998. 我是1998年认识他的。
You’ll soon get to like the work. 你不久就会喜欢这份工作的。
2．Why should students be careful smelling from bottle?为什么学生在闻从瓶子里冒出来的气味时要小心？
be careful doing 的意思是“做某事仔细或小心”，be careful 后面常跟with, in, about 等介词短语，也可跟to do 或从句。
e.g. People should be more careful about the thing they say.大家对自己说的话应该谨慎。
Please be careful with those plates! 那些盘子要十分小心。
Be careful in / about crossing the road. 过马路要留神。
Be careful not to hurt her feelings. 当心别伤了她的感情。
Be careful that the medicine is kept away from children.要小心把药放在孩子拿不到的地方。
3．What is to be done when something gets into your eyes?如果你眼睛里进了东西，该怎么办？
“be ＋to do”结构表示安排、命令、职责、义务、目的、用途、可能性、命中注定等。
e.g. We are to meet at the school gate. 我们约定在校门口碰头。（安排）
You are to be back by 10 o'clock.你得在10点钟前回来。（命令）
I am to inform you that the meeting will be held in Hangzhou.
我谨通知你会议在杭州举行。（职责）
A knife is to cut with. 刀是用来切割的。（用途）
They were never to meet again. 他们注定以后永远不见面。（命中注定）