是
1. 用only+状语提前，句子部分倒装.
eg: Only after we asked him for three times did he agree to join us. 我们请了他三次，他才同意加入我们。
Only in my own room can I read books.
2. 用only强调主语
eg: Only you can persuade him to give up smoking.
另：很抱歉，这里想指出楼上这句话里的语法错误，无它意，只是学习交流：Only when you go abroad can you see the world. （only 引导时间状语从句,缺连词。）
或者,Only when going abroad can you see the world.(现在分词作状语，共用主句主语you。)