"is difficult for me" vs. "is difficult to me"

Question

As an ESL learner, I guess I'm not the only one said something like

"English is difficult for me"

or

"English is difficult to me"

I was trying to say that learning English is not easy.

to convey the idea, should I use "for me" or "to me"?

Ngram Viewer shows the former is much more common.

The question is that the latter is just less common or grammatically incorrect?

Sometimes, using uncommon expression is a tip to get attention while using incorrect grammar is embarrassing.

I've gone through the post Should I say "It's difficult 'to me' / 'for me' to express my self"?

which doesn't explicitly claim "to me" is wrong and explain why clearly. Can somebody help me?

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Another use also confuses me. I have some difficulty distinguishing "to me" and "to my ear". I understand the meaning, I just don't understand the usage.

In other words, why is "to my ear" wide recognized while "to me" is not as common, may be even incorrect?

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I'm also confusing is + adjective + to/for me with "sounds good to me", as "sound/feel/look" and "to be" all are the predicate of a sentence for that kind of situation.

Answer 1

There are three possible interpretations of the second sentence. All of them are technically grammatical, but none of them make for a natural sentence.

In the following, my use of ✘ is not to indicate that it's ungrammatical, but that it's unusual and not normally used.

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1. a1) ✔ Seafood is harmful to me.
1. a2) ✔ English is harmful to me.

These sentence are fine, especially the first one. (Thinking of English as being harmful is slightly odd, but it's still understandable.)

1. b2) ✘ Seafood is difficult to me.
1. b2) ✘ English is difficult to me.

But if you replace harmful with difficult, it no longer really makes sense. Things are not normally difficult to other things.

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2. a) ✔ To me, ^{(in my opinion)} English is difficult.

This is more of a general statement, saying that English is difficult objectively, rather than only saying it's difficult in terms of your own use.

This also makes sense, but this interpretation is only normal if to me is put at the front of the sentence, typically followed by a comma.

2. b1) ？ English is difficult, to me.
2. b2) ✘  English is difficult to me.

If this interpretation is used, having to me at the end is semantically fine, but unnatural in its order. Although, note how the addition of the comma actually makes this interpretation more understandable.

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3. a) ✔ I find it difficult to use English.

This makes sense, and it has the same meaning that's being expressed in the question.

3.. b) ✘ English is difficult to me.

But the phrasing in the original version is not something that would normally be used. As the Google Ngram Viewer results show, the use of for is much more common.

What makes the use of to more unusual is that there are other interpretations that can prevent you from being totally sure what is meant, even if this third interpretation is the most likely.

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No matter which way you interpret the sentence, the use of to is either uncommon or outright strange.