if I have 和If I had的区别

if I have 和If I had的区别 if i have和if i had的用法 If I had to和If I have to的区别 if I saw you, I had remembered you.和if I saw you, I had have if I were和if I am的区别 he would have if i had asked If I had known that,I could have helped you.had和known怎么都是过去式 if i had my If.I.Had.You If i had studied if i had. i would have这是什么语法? if i had worked hard,i would have succeed