有个单词写错了,应当是Only when you really lose someone,you fully realize how much you value him.
这个句子如果没有逗号,就要倒装,即：
Only when you really lose someone do you fully realize how much you value him.有逗号就倒装喽？ 单词没写错呀。倒装应该是 will you realize 吧？对对对，你说得对。这是一般将来时。主将从现，主句是用will you realize。没有逗号就倒装。