Correct use of the word "I"

English as a Second Language English Vocabulary, Grammar and Idioms
1

Joan and I went shopping? ( Is this correct)?

Joan and me went shopping? ( Is this correct)?

Joan, Ellis, Vaughn, and me went to dinner. ( Is this correct)?

Joan, Ellis, Vaughn, and I went to dinner. ( Is this correct)?

2

In both cases it should be “I” because it is used as part of the subject of a sentence.

3

As Tort says, because it is a subject you need ‘I’. You would use ‘me’ if it were an object within the srntence.

Compare hese:

Joan and I went shopping.

Joan went shopping for me.

Joan and I went to dinner.

Joan went to dinner before visiting me.