We use so and neither to indicate similarity between or among people
or things. We use so with affirmative sentences and neither with
negative sentences.

I have a red Ferrari. So does Jane.
Mary doesn't know how to drive. Neither does Tom.
The girls are wearing blue. So is Max.
Fred isn't very nice. Neither is Joe.
The green car is ugly. So is the yellow one.
Mary won't talk to me. Neither will Tom or Susan.
Steve can surf very well. So can I.

So and Neither - General

f we use the present or simple past tense forms of most verbs in the
first sentence, we follow so or neither by the appropriate form of DO.

Max swims everyday. So do the other boys.
Mike doesn't play soccer. Neither does Mary.
Jill likes ice cream. So does Nancy.
John doesn't eat brocolli. Neither does George.
Steve escaped from prison. So did Mary.
You didn't eat the last piece of cake, and neither did I.

So and Neither with BE

If we use BE in the first sentence, we follow so or neither by the appropriate affirmative form of BE in the following sentence.

Max is from California. So is Mary.
Joe isn't very tall. Neither am I.
Those books are old. So is this one.
We are not happy. Neither is Sam.

So and Neither with Modals

If we use a MODAL(will, would, can, could, may, might, must, shall, should, do) in the first sentence, we use the affirmative form of the same modal after so or neither.

Joe can swim. So can Mary.
Sam won't go. Neither will Max.
Mary should study more. So should Joe.
Jill couldn‘t lift the box. Neither could Jack.
Tom wouldn't eat the cereal. Neither would Mikie.

So and Neither with Perfect Expressions

If we use a perfect expression (HAVE + Verb - en as in have eaten, had stolen, will have bought) in the first sentence, we follow so or
neither by the appropriate form of HAVE or MODAL + HAVE.

Bill has eaten too much. So has Mary.
Bill had eaten too much. So had Mary.
Bill May have eaten too much. So may have Mary.
Bill will have eaten too much. So will have Mary.