“今天我请客！”这句话经常听到，豪爽至极，英语中怎么表达这个意思呢？
1. something be on me：used when you are telling someone
you will pay for their drinks, meal etc. 某个东西我买单
例：
（1）Order whatever you like--this is on
me.（喜欢什么尽管点，今天我请客。）
（2）Put your money away--the drinks are
on us.（你把钱收起来，饮料钱我们给。）
（3）美剧《老友记》S01E14：情人节，Joey和Chandler约了两个女生一起进行double-date，结果Joey和他的女伴要先走，Joey觉得对不住Chandler，于是说“这顿饭我请！”。
Joey: I'm outta here. Here's my credit
card. Dinner's on me. I'm sorry, Chandler.
2. my treat 我请！
例：
Let's go out for dinner - my treat this
time.（我们出去吃，这次我请。）
3.在酒吧请喝酒
（1）buy sb a beer etc.
例：美剧《老爸老妈浪漫史》S01E02：
Ted: I'll buy everyone a beer.（我给大家买啤酒去。）
Robin: I’ll help carry.（我来帮忙拿。）
（2）buy a round: to buy drinks for the people you are with in a bar （在酒吧里）请你的所有朋友喝酒
例：
Joe bought a round of drinks for everyone.（乔给每个人买了酒。）
（3）It's my shout.
注意：这是英式英语的口语表达。
例：
No, it's my shout—what are you drinking? （我来买，你喝什么？）
4. put it
on my tab 记在我账上
例：
Put it on my tab.（记在我账上。）
He ordered dinner and asked for it to be
put on his tab.（他点了餐，说记在他账上。）
5. pay 付钱
例：
If I go out for a meal with my parents,
they always pay.（每次和爸妈出去吃饭，都是他们付钱。）
When we got to the ferry, Eddie took out a
five-dollar bill and paid for Terry and me.（到了渡口，艾迪拿出$5，帮我和泰瑞都付了钱。）
Who paid for your driving lessons? （你学车的钱谁出的？）
My company paid for me to go to evening
classes.（公司出钱让我去上夜校。）
6. treat:
①to buy or do
something special for someone that you know they will enjoy表示“买一些某人肯定会喜欢的东西，或做一些某人肯定会喜欢的事情”
例：
We treated Sally to lunch at the Savoy.（我们在Savoy酒店请莎莉吃饭。）
Once a year, I treat myself to a ski trip.（每年，我都去滑雪，犒劳自己。）
②to buy
something such as a meal for someone because you want to celebrate something表示“想庆祝某事，而跟某人一起吃饭”
例：
As it's my birthday, I thought I'd treat
you.（今天是我生日，所以我想请你吃饭。）
7. pick up the tab: to pay for
something, especially when it is not necessarily your responsibility or duty to
do this表示“不一定有义务要付钱，可是却付钱了”
例：
We all went out to dinner, and Adam picked
up the tab.（我们一起出去吃的饭，亚当付了钱。）
Usually the book publisher, not the author,
picks up the tab for a publicity tour.（通常是出版商出钱做新书推广，而非书的作者。）