if only
a) used to express a strong wish, especially when you know that what you want cannot happen
If only he had talked to her sooner! If only I weren't so tired！强调语气，虚拟，知道是不可能发生的
b) used to give a reason for something, although you think it is not a good one
Media studies is regarded as a more exciting subject, if only because it's new.
虽然你知道这似乎看起来不能算个好理由，但怎么着也算个理由把
只能把if only当做某种修饰成分修饰着because | 
