So/Neither + auxiliary verb

Question

1

1. Vinay plays cricket, so does Ashok.

We use so+ auxiliary verb when second person( Ashok in case of above sentence) shows agreement with positive sentence. Here in 1 sentence i have no confusion.

2. He can speak French, and so can speak German.

What about this sentences. It seems correct grammatically correct but doesn't make any sense. French and German are two different language. So if one can speak French than it is not necessary that one can also speak German. So i am confused if it is correct way to write this.

2.

1. I don't like coffee, neither does he. This sentence is correct.

2. I seldom went to Christmas parties, neither did he.

Is the second sentence correct? When i read this sentence It seems "neither" does't fit here. I mean it doesn't fit in the flow of a sentence (it's look like breaker on road when we have to slow our car).

Answer 1

So can be used to say that another subject is doing something "as well" or "in addition." - you can keep things in one sentence with so but not with as well or in addition (so that's why it happens in speech often):

Vinay plays cricket, and so does Ashok.

Vinay plays cricket. Ashok does as well.

But if there's a second action, so takes on the meaning of because of that:

He can speak French, and so can speak German.

He can speak French and because of that he can speak German.

Don't use so at all, simply say

He can speak French and German.

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The problem with this:

I seldom went to Christmas parties, neither did he.

is that while "seldom went" has the meaning does not go that often, it's not a verb in negative form, so neither doesn't correctly link back to it.

You can either change "seldom went" to a negative verb, add "he" to the subject of the sentence, or make "neither did he" a full sentence with "either". ("Seldom" is one of those words you generally don't want to overuse by using it in two sentences in a row.)

I didn't tend to go to Christmas parties, neither did he.

He and I seldom went to Christmas parties.

I seldom went to Christmas parties. He didn't usually show up to them either.

Answer 2

the adverb "so" is used in different senses. You can also use it to mean "in the same way, too/as well" when you want to say that something that has just been said about one person or thing is true about another. But it can only be done when both clauses of a sentence are in the affirmative, not in the negative. In the negative sentences, we use "neither instead of "so".

Vinay plays cricket, and so does Ashok.

He laughed, and so did I.

He's been ill, and so has his wife.

All these sentences are correct as both clauses are in the affirmative, but the following sentence is grammatically incorrect because the first clause is in the affirmative and the the second one is in the negative:

I seldom went to Christmas parties, neither did he.

The correct sentence is "I seldom went to Christmas parties, and so did he". The adverb "seldom"is actually a negative-like word that means "on a few occasions (not often), so we can't consider the first clause of the sentence to be purely negative and use neither in the second clause.

He can speak French, and so can he German.

As for this sentence, although it makes no sense as pointed out by the OP, but it's grammatically correct, in which the "so" has been used to mean "with the result". "As he learned, so did he teach (THE FREE DICTIONARY). Maybe, the two languages are so closely related that when you know French you can also speak German. In that case, the sentence will make sense. I don't know.