if only用法及其他

1.是的.用一个例子概括你看：
以你要求的几种时态的虚拟语气：我要是在这儿就好了.
现在时：If only I were here.
过去时：If only I had been here.
将来时：If only I would be here.
动词向前推一个时态.
2.不对,还可以用who,whom,whose,只不过可以省略
比如：
.--where is your english book?just see what a mess in your schoolbag!
--The one whose cover is red,it’s easy to find anyway .
The one (whom)you referred to is my son. 你指的那个人是我儿子
The one (that) you bought is much better.你买的那个比较好.
这里面省略了做宾语的引导词that /which/who(m),
3.不是,比如：I'm feeling better nwo.我现在感觉好点了.feel不就是用正在进行了.
相信我,我是英语六级,英语老师,嘿嘿.