Betol
比妥耳, 水楊酸 β-萘酯
??? 情景例句
When will you be through with your homework?
你的家庭作業(yè)什么時候可以做完？
That is a serious matter.
那是件嚴(yán)重的事。
There is a boat in the river.
河里有一條船。