虚拟语态看看这个句子,摘自百度百科：在if only 引起的感叹句中需用虚拟语气.谓语动词用过去式或过去完成式.例如：

1）对过去情况的虚拟,句子用过去完成时.
如：If only I had taken his advice!
2）对现在情况的虚拟,句子用一般过去时/过去进行时.如果是be动词的话用were
如：If only I were a billionaire!
If only I were dreaming!
3）对将来的情况虚拟,句子用过去将来时.
如：If only I would fly tomorrow!