she treats me as if i was her daughter.

were 和 was 都可以用

The subjunctive mood, always weak in English, has been dwindling away for centuries until it has almost vanished. According to traditional thought, statements about the conditional future such as “If I were a carpenter . . .” require the subjunctive “were”; but “was” is certainly much more common. Still, if you want to impress those in the know with your usage, use “were” when writing of something hypothetical, unlikely, or contrary to fact.
The same goes for other pronouns: “you,” “she,” “he,” and “it.” In the case of the plural pronouns “we” and “they” the form “was” is definitely nonstandard, of course, because it is a singular form.

怎么可能？ 任何时候 I 后面也都WAS, 不能WERE的

不一定i后面一直是was的，if i were you如果我是你的话

虚拟语气里没有was啊 不都用were么

这是虚拟语气的规定，虚拟语气是虚假的，表示该动作或事件不可能发生，那么be动词就用were

回复：8楼
8楼正解帝哇
表示同意....

虚拟语气里的were如if i were you,这时的were表示i本身不是you，也不可能成为you的事实。
有可能成为或者发生在自己身上等就用was
仅供参考

虚拟语气都用were 好吧！！

was and were
both are correct

虚拟语气从句中be动词只用were

只要是虚拟语气，用的都是were 比如： If I were a boy.....

They couldn't be who they was 为什么要用was，不用were 我一直都不懂 头都想炸了

根据薄冰《高级英语语法》（世界知识出版社），正式语体中用were，非正式语体中用was。但是，在参加英语考试时，应该用were。

口语中不用这么较真

虚拟语气是一种古体形式，随着英语的发展，虚拟语气有逐渐被陈述语气替代的趋势。但现代英语仍然保留了相当的虚拟语气形式，虽然有的句型有模糊地带。也就是说在正式语体和非正式语体之间有区别。一般英语语法考试都是以正式书面语为准，所以要选择正式的形式。
与事实相反的虚拟语气需要用be的时候，正式语体都用were，但非正式语体中主语是第一、三人称单数时，常用was代替were。考试时还是要选择were。但在if I were you这个句式中，永远都不能用was。
She treats me as if I was/were her daughter.

另外，
He looks as if he was/were eating something.(虚拟语气。他有可能真的在吃东西）
He looks as if he is eating something. （陈述语气。他只是嘴在动，其实没有吃东西）
If it rains tomorrow,.....陈述语气（现代英语）
If it rain tomorrow...虚拟语气（有可能但未必是事实。非常正式，古体）
If it rained/were to rain/should rain tomorrow...虚拟语气（与事实相反）