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She is good in tennis, because while he is not is the most popular phrase on the web.

She is good at tennis, because while he is not 1103,000,000 results on the web	She is good in tennis, because while he is not 1159,000,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
They know about us: that you're good at tennis, that you... She is good at speaking English. She is good at playing the guitar. But she is good at her job? Mr. Smith, because my son is good at football... he has opportunities that otherwise would not be his. I mean, no one actually thought he was saying goodbye to tennis for good, because that's a crazy thing to say when retiring. She is so good at making people believe she is good with people. She's good at tennis too.	Lettered in tennis, squash, and served as editor of the school newspaper. In tennis, you attack at the point of weakness! Dude, you had to play me in tennis, now horse. I mean, no one actually thought he was saying goodbye to tennis for good, because that's a crazy thing to say when retiring. But in tennis, they're forced to interact. Yesterday they didn't play tennis, because it rained. She is all that is good in the world. I mean, that's not old, but in tennis, that's old.

She is good at tennis, because while he is not

1103,000,000 results on the web

She is good in tennis, because while he is not

1159,000,000 results on the web

More popular!

They know about us: that you're good at tennis, that you...
She is good at speaking English.
She is good at playing the guitar.
But she is good at her job?
Mr. Smith, because my son is good at football... he has opportunities that otherwise would not be his.
I mean, no one actually thought he was saying goodbye to tennis for good, because that's a crazy thing to say when retiring.
She is so good at making people believe she is good with people.
She's good at tennis too.

Lettered in tennis, squash, and served as editor of the school newspaper.
In tennis, you attack at the point of weakness!
Dude, you had to play me in tennis, now horse.
I mean, no one actually thought he was saying goodbye to tennis for good, because that's a crazy thing to say when retiring.
But in tennis, they're forced to interact.
Yesterday they didn't play tennis, because it rained.
She is all that is good in the world.
I mean, that's not old, but in tennis, that's old.