if would 的文法問題?

If:-You use if in conditional sentence to say event or situation might happen
eg:-She gets upset if I exclude her from the party.
eg:-What I did was right and if I had done anything wrong it would have been right.
eg:-Are you a student with a skill for coming up with great ideas? If so, we would love to hear from you.
You can use if in polite requests at the beginning of a clause when you ask someone to do something.
eg:-I wonder if I might have a word with Mr.Dragon ?
eg:-I wonder if you would be kind enough to give me some iNFO ?
eg:-If you married, I would stay happy; all the property would be yours.
Nobody would use it for marriage.

1. 對未來極大懷疑，條件子句不分人稱與數，一律用should（should在這裡不含有應該的意思）:
If you "should" marry me, all the property would be yours.（我根本不敢相信你會跟我結婚，完全無望，所以條件是虛構的）
柯旗化《新英文法》pp.396~7

2. I would be very grateful if you "would" grant my request.（這是比較委婉的請託，用假設語氣動詞組，表示我尚抱有一線希望）see p.1607《新世紀英漢辭典》
If you "would" marry me, all the property would be yours.（用would，因我對跟你結婚這件事尚抱有一線希望。這也是假設語氣動詞組，但屬於一種委婉的要求）
"Would" you marry me?（用假設語氣動詞組，以表示委婉的請求：可以嗎？）
"Will" you marry me?（用直述語氣動詞組，口氣直接了當）

If it rains tomorrow .I will stay home. 未来假設句，發生机率50%。另改寫之未來句，發生机率萬分之一。例如: If it should rain tomorrow, I would stay home.這種用法是幾乎不可能發生。若是本句寫法If you would marry me, all the.property would be yours. 就單純的指與現在事實相反的假設句。所以就不能翻成如果未耒嫁始我，所有財產就歸妳。