If only...!真希望……!若是……那该多好啊!
之后常用虚拟语气,例如：
(1) 谓语动词用过去式表现在：如：
例：If only I knew his name!要是我知道他的名字就好了.
(2) 谓语动词用过去完成时表过去：如：
例：If only we had followed your advice!我们要是采纳你的意见就好了.
(3) 谓语动词用could/would表将来：如：
例：If only I could see him again!要是我能再看到他多好啊!
If only she would accept my invitation!