I wish I could 和 I hope I can 有分別嗎？

 最近講過如何用 (wish + subject + past subjunctive) 這種句子結構去表達「對現狀的遺憾」(present regrets)：

http://grammarfun101.blogspot.com/2011/08/i-wish.html 

譬如說： 

I wish I had enough money to buy a Ferrari.
He wishes he owned the cinema so that he couldwatch movies every day.
She wishes the university were in her city.
He wishes he could do something to help the poor.
I wish I had the answer to your question, but I don't.
I wish I knew everything under the sun. 

牛津高階字典第六版是這樣解釋 "wish" (verb) 這個字： 

"To want something to happen or to be true even though it is unlikely or impossible." 
「希望不大可能的事發生；懷著不可能實現的願望。」

跟 "to wish" 不一樣，"to hope" 的意思是：希望某可能發生的事發生。牛津字典是這樣解釋 "hope" (verb) 的：  

"To want something to happen and think that it is possible." 

因為 "to hope" 是用來表達對可能發生的事的期望，所以 "hope" 之後的動詞我們不用帶有不可能意味(unlikelihood) 的 past subjunctive：


I hope you can come to my birthday party.
She hopes she can go to London this year.
My brother hopes he gets the job. 
I hope I will get a raise next year so that I will be able to afford a new car. 

現在 "to wish" 和 "to hope" 的分別應該很明顯了。

如果你想說「我希望我能飛」，你應該說： 

I wish I could fly. 

而不是： 

I hope I can fly.