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surprised by your reaction is the most popular phrase on the web.

surprised at your reaction 1123,000 results on the web	surprised by your reaction 1139,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
We are surprised at Russia's reaction. I'm surprised at that reaction, but I am. I am very surprised at the reaction in the press to last night's developments. I was surprised by my reaction. I am surprised by the reactions we hear along these lines, sometimes from the foreign ministers too, the Dutch minister amongst them. Forgive me if I'm a little surprised by your reaction. Sorry. His reaction surprised me. I'm very surprised by this reaction of yours.	Forgive me if I'm a little surprised by your reaction. I'm surprised at that reaction, but I am. Sorry. His reaction surprised me. I'm very surprised by this reaction of yours. I was surprised by my reaction. We are surprised at Russia's reaction. I am surprised by the reactions we hear along these lines, sometimes from the foreign ministers too, the Dutch minister amongst them. Well, were you surprised by his reaction?

surprised at your reaction

1123,000 results on the web

surprised by your reaction

1139,000 results on the web

More popular!

We are surprised at Russia's reaction.
I'm surprised at that reaction, but I am.
I am very surprised at the reaction in the press to last night's developments.
I was surprised by my reaction.
I am surprised by the reactions we hear along these lines, sometimes from the foreign ministers too, the Dutch minister amongst them.
Forgive me if I'm a little surprised by your reaction.
Sorry. His reaction surprised me.
I'm very surprised by this reaction of yours.

Forgive me if I'm a little surprised by your reaction.
I'm surprised at that reaction, but I am.
Sorry. His reaction surprised me.
I'm very surprised by this reaction of yours.
I was surprised by my reaction.
We are surprised at Russia's reaction.
I am surprised by the reactions we hear along these lines, sometimes from the foreign ministers too, the Dutch minister amongst them.
Well, were you surprised by his reaction?