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he is a good swimmer is the most popular phrase on the web.

he swims well 132,100 results on the web	he is a good swimmer 1239,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
The 15m pool allows to swim well and therefore a local olive trees of sight setting. I have the impression, Commissioner, that you could swim well with sharks if you had to. Watch me, I can't swim well. You can't swim well enough, darling. He could swim very well when he was young. Even if you swim well, we look pathetic to sharks. I could swim well when I was a child. They can swim well enough, but usually prefer to gallop across the muck... on the tips of their fleshy, little arms.	I knew you'd be a good swimmer. He isn't a good swimmer, and it's a little too soon... for him to be out here unsupervised. No, I'm a good swimmer. Nevertheless he is a good swimmer. And I'm not a good swimmer. No, I'm a good swimmer. I'm a good swimmer, Philip. They emptied the pool because I'm not a good swimmer.

he swims well

132,100 results on the web

he is a good swimmer

1239,000 results on the web

More popular!

The 15m pool allows to swim well and therefore a local olive trees of sight setting.
I have the impression, Commissioner, that you could swim well with sharks if you had to.
Watch me, I can't swim well.
You can't swim well enough, darling.
He could swim very well when he was young.
Even if you swim well, we look pathetic to sharks.
I could swim well when I was a child.
They can swim well enough, but usually prefer to gallop across the muck... on the tips of their fleshy, little arms.

I knew you'd be a good swimmer.
He isn't a good swimmer, and it's a little too soon... for him to be out here unsupervised.
No, I'm a good swimmer.
Nevertheless he is a good swimmer.
And I'm not a good swimmer.
No, I'm a good swimmer.
I'm a good swimmer, Philip.
They emptied the pool because I'm not a good swimmer.