SO - NEITHER

SO

SO is used to show agreement with affirmative statements by, or concerning, another person.

SO + Auxiliary + Subject (pronoun) :  So do I

Remember :
The Auxiliary in the response must agree with the verb tense in the original statement.

Here are some examples :

Speaker A	Speaker B
Charlie likes chocolate	So do I.	(= I like chocolate too.)
Emma lives in London.	So does Amanda.	(= Amanda lives in London too.)
Alex can swim.	So can Jenny.	(= Jenny can swim too.)
Pedro is good at sports.	So is Rafael.	(= Rafael is good at sports too.)
Our teachers are very strict.	So are ours.	(= Our teachers are very strict too.)
Enzo would love to work in Paris.	So would I.	(= I would love to work in Paris too.)
Alex will be angry.	So will I.	(= I will be angry too.)

NEITHER

NEITHER is used to show agreement with negative statements.
NEITHER can be replaced by NOR with no change in meaning.

Neither + Auxiliary + Subject (pronoun) :  Neither do I (Nor do I)

Remember :
The Auxiliary in the response must agree with the verb tense in the original statement.

Here are some examples :

Speaker A	Speaker B
Sam doesn't want to go out.	Neither do I.	(= I don't want to go out either.)
Wendy can't cook.	Neither can I.	(= I can't cook either.)
Jason doesn't have a ticket.	Neither does Tom.	(= Tom doesn't have a ticket either.)
I can't speak Chinese.	Neither can Sue.	(= Sue can't speak Chinese either.)
Peter hasn't finished yet.	Neither has Tom.	(= Tom hasn't finished either.)
Meg couldn't come today	Neither could Sue.	(= Sue couldn't come today either.)
Dad won't pay attention.	Neither will Mum.	(= Mum won't pay attention either.)