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surprised to see is the most popular phrase on the web.

surprised at seeing 1278,000 results on the web	surprised to see 132,200,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
As you're seeing this gel magnet for the first time, if you assume that all magnets had to be hard, then seeing this surprised you and it changed your understanding of the way magnets could work. I'm surprised at your lack of concern. She was not surprised at seeing him there. I'm really surprised at Derek and... I'm sorry. There was practically no blood. I was surprised at that. You'd be surprised at what you can do. Are you surprised at seeing me bowing you with just one hand? Why should I be surprised he was seeing other girls?	Don't act so surprised to see me. I'm really surprised to see you here. I guess you're probably surprised to see me here, Wayne. So... I'm surprised to see you, Casey. No doubt you're surprised to see me, John Sheppard. Yes, I am surprised to see you. Tommy, I'm surprised to see you.

surprised at seeing

1278,000 results on the web

surprised to see

132,200,000 results on the web

More popular!

As you're seeing this gel magnet for the first time, if you assume that all magnets had to be hard, then seeing this surprised you and it changed your understanding of the way magnets could work.
I'm surprised at your lack of concern.
She was not surprised at seeing him there.
I'm really surprised at Derek and... I'm sorry.
There was practically no blood. I was surprised at that.
You'd be surprised at what you can do.
Are you surprised at seeing me bowing you with just one hand?
Why should I be surprised he was seeing other girls?