if only 与 I wish一样，也用于表示与事实相反的愿望，其后所虚拟语气的时态与 wish 后所接时态的情况相同：
If only she had had more courage! 她再勇敢一些就好了。
If only it would stop raining! 雨要是停了就好了。
If only he didn’t drive so fast. 但愿他车没开得那么快。
If only I were [was] better looking. 要是我长得漂亮些就好了。
If only I had listened to my parents! 我要是当时听了父母的话就好了。
If only she would go with me! 她要是愿意和我一道去就好了!
【友情提示】if only 通常独立使用，没有主句。
From:https://www.zgghmh.com/CET-6/20007561.asp