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Carol: Bob, how did the baking go?
Bob: slow at first, but we're getting the hang of it.
Carol: once you learn the ropes, it becomes second nature.
Bob: to tell you the truth, I thought that baking 2,000 cookies would be a pain in the neck. But we managed to round up some helpers, and it was a piece of cake.
Carol: well, thanks for coming in person with cookies.
Bob: do problem. When will you need more?
Carol: it depends on how many we sell today.
Bob: how many do you think you'll sell?
Carol: maybe 500, maybe 2,000. your guess is as good as mine. In any case, I'll keep you posted.
Bob: okay. Just give me a ring as soon as you know.
实战美国俚语
At first: in the beginning 一开始，最初

To get the hang of sth: to learn how to do something; to acquire an effective technique 掌握了…的要领，了解…的用法,找到了诀窍

To give someone a ring: to telephone someone 打电话给某人

In any case: whatever the fact is; certainly 不管怎么说

In person: personally; in one's physical presence 亲自

To keep posted: to provide up-to-date information 及时报告

To learn the ropes: to learn the basics熟悉某一行业，了解内情

pain in the neck: an annoyance 头痛的事

Piece of cake: very easy 很简单

To round up: to gather people together 聚集，集合

second nature: a behavior that has been practiced for so long, it seems to have been there always第二天性，习性

Your guess is as good as mine: I don't know; I don't know anymore than you do 我也不知道