英语有哪些日常生活中比较常用的口语？

hello 你好 by the way顺便问一下

你去买一本常用口语900句就可以了

有很多了，建议去看初中或小学的课本，也可以随便找本日常用语的英语书来看。
Hello!How do you do?How are you?What's up? ......

口语太多太多了。。。需要看用在什么场景了。 列举了以下两个常见场景供参考。如果想到其他场景需要，再问。
求助时：
Could you . . . . (for me) ?
Would you please . . . ?
Would you mind V+ing . . . .?
Could you possibly . . . ?
Okay, no problem.
Sure, I'd be glad to.
Sorry, I'm (kind of) busy now.
I'm sorry. I don't have time right now.
Do you have a minute?
Can you spare a few minutes?
Could you do me a favor?
Could I ask you a favor?
Can I ask you to . . . ?
I need some help (if you have time).
(If you're not busy) I could use your help.
道歉时：
I'm sorry.
I made a mistake.
Please accept my apologies.
I'm sorry. I didn't mean to . . .
(I'm) sorry. I didn't realize that . . . .