Of course. Pirates don't worry about such things and they make their own rules.
"He does not", or, "he doesn't speak English" would be correct. It would never be 'he do not speak English,' as that is incorrect grammar.
I don't know what he likes, but maybe he likes to speak and type in incorrect grammar like you.
Incorrect grammar is a handicap for a speaker because of the way it makes others view him or her. Incorrect grammar is often associated with lower-class people, so using it may prejudice the listeners against the speaker. Also, incorrect grammar can be distracting if it makes it difficult to understand what the speaker means.
The grammar in the question is correct.
This question is incorrect grammar.
incorrect grammar
different pirates speak different laguages.
syntaxtically incorrect
It's not incorrect, but could probably be said more succinctly.
No, "I remember nothing" is not incorrect grammar. It is a complete sentence where the subject ("I") and the verb ("remember") are properly used.
Yes. It can be set by the user to check grammar in addition to spelling.
That sentence is grammatically correct.