So, neither

A is or does the same as B

To say that A is or does the same as B, we can use so + auxiliary verb + subject for affirmative sentences and neither + auxiliary verb + subject for negative sentences.

A: “I am from London.” B: “So am I.” (=I am from London too.)
A: “I’m not tired.” B: “Neither am I.” (=I am not tired either.)

What auxiliary verb do we need?

After so/neither we use the same auxiliary or modal verb as in the first sentence: be, do, have, can, will, must, etc.

A: “Tomas is not going to the party.” B: “Neither is Sally.”
A: “I’ll be here at 7.” B: “So will I.”
A: “Lisa can play the guitar.” B: “So can Tim.”

When there isn’t an auxiliary or modal verb in the first sentence, we use do/does for present and did for past.

A: “I want to leave.” B: “So do I.”
A: “George loves chocolate.” B: “So does Bruno.”
A: “I went to bed very late.” B: “So did I.”

nor = neither

We can use nor instead of neither.

A: “I wasn’t ready.” B: “Nor/Neither was I.”

neither is negative

Neither/nor is a negative word, like not. For this reason, the auxiliary verb after neither should be affirmative.

A: “I didn’t see the film yesterday.” B: “Neither did I.” (NOT ~~Neither didn’t I~~)
A: “Ray couldn’t answer the question.” B: “Neither could Jimmy.” (NOT ~~Neither couldn’t Jimmy.~~)

too, either

Another way of saying that A is or does the same as B, is the use of too or either at the end of the sentence. We use too for affirmative sentences and either for negative sentences.

A: “I want to leave.” B: “I want to leave too.”
A: “I didn’t go.” B: “I didn’t go either.”

so-too, neither-either – tables

so, neither, too, either

neither, either