例句
It was an electroscope which contained a small amount of radium.
这是一个验电器，其中载有少量的镭。
As there was already pre-charge applied to the electroscope , an additional little charge caused reaction.
由于已经有预充电适用于验电器，额外收取很少引起的反应。
In today's experiment you are going to build an electroscope to measure the static electricity of various household objects.
今天的实验中，你会自己做一个验电器，来测量看看不同的家用品各会产生多少静电。