In English, we use connector adverbs like ‘neither’ and ‘either’ when we want to introduce another negative idea into the conversation.
We use ‘neither’ when talking about actions we haven’t done or don’t like:
Alex can’t speak Spanish. – Neither can Dia.
(Notice that the response is in the same pattern ‘can’- ‘can.’ Also, ‘neither’ is negative, so the following word should be positive. In other words, ‘neither’ automatically makes the sentence negative, like ‘never.’)
Muslera doesn’t understand what the coach says. – Neither does Joe.
A: I don’t like spaghetti.
B: Neither do I.
A: My wife doesn’t like cooking.
B: Neither does my wife.
Unlike ‘neither,’ ‘either’ is used at the end of a sentence:
A: I don’t like pizza.
B: I don’t, either.