其实你真的和说英语的人说 I can't swim.没有人会误会你的.会知道你不会游泳. 你实在是担心的话,可以说成 I don't know how to swim. 通常问别人会不会游泳都说 Can you swim? 好象较少会说 Do you know how to swim?不过也可以 你会拼写这个单词吗? 1Can you spell it? 2Do you know how to spell it?
没错,就是 i can't swim 不要太纠结于语法了,很多时候的口语没有那么严谨 如果你还不信,专门给你找了一个链接,看看native english speaker是怎么说的 :) http://ask.metafilter.com/100878/Im-24-and-cant-swim-Is-there-a-20somethings-swim-class-in-NYC