Hi. I am writing my master thesis and need to do a kind of a test with native speakers. Could you take a look at the following sentences and insert RATHER, PRETTY, FAIRLY or QUITE where it seems more natural to you. There is no right or wrong. I simply need the statistics. Please, specify the country of origin and your age. Thanks in advance.

1.I was _____ surprised to see him with his ex-wife.
2.He was limping _____ badly.
3.I got a letter from Sylvia ______ recently.
4.The food in the cafeteria is usually ___ good.
5.She still looks ______ miserable.
6.I’m ______ sure he’ll say yes.
7.The house had a ____ large garden.
8.She speaks English ______ well.
I'd say all 4 are acceptable in each of your examples.
I live in Canada, but I originated in Britain.

Just as an aside, I'd say in the US we usually (but not always) reverse the article and adverb when "quite" is used: The house had quite a large garden.

Are we messing up your test? We native speakers are famously incorrigible!
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Some native speakers might be able to list a hierarchy of these terms, but I use them pretty much interchangeably. I do agree with Avangi's suggestion about inversion in the case of quite with an article, such as a.

His garden is quite large ~ He has quite a large garden.
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