Why are commas so confusing in English?

They aren't. They are just used differently than they are in Estonian. Basically (see references, below for more details):

1. Use a comma to separate things in a list: bananas, apples, and oranges (this last comma before "and" is debateable and depends on your style guide. To use it or to omit it is equally correct, but you need to look it up in the publication guidelines, if you have them. If not, just be consistent and use the same rule throughout your text).

2. Use a comma between two independent clauses joined together by a conjunction (remember "Conjunction Junction"?): She came to class, and she paid attention.

3. Use a comma after an introductory phrase or adverbial that has been placed at the beginning of the sentence: In fact, I was not sure about whether or not the weather would get better. However, we went outside anyway. In the middle of the night, it snowed three feet.

4. Use commas to set off non-essential clauses: Jennifer, who is from Wyoming and loves to be outside, was our English teacher for the seminar on Friday.

5. Use them with dates, addresses, geographical terms when necessary (see sources, below)

6. There are some other uses for commas, but I think these are the most important ones.  Please check out the links if you continue to be curious!

Which resources did you use to find the solution? Were the resources useful?