1. 長劃符號
此類符號專用來連接兩句,同時強調第一個子句,以補充意思的不足,相當於『也就是說』或『換句話說』的意思。
There is hardly anything David doesn't know —— he is a child prodigy.
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There is hardly anything David doesn't know. That is to say,
That is,
In other words,he is a child prodigy.
(大衛幾乎無所不知。換句話說,他是個神童。)