I have heard the following usage of 'so' quite frequently in Indian schools:
He was sick so he did not come.
Isn't this incorrect? I prefer this usage:
He was sick, and so he did not come.
My first part of the question is some kind of attestation on whether the first usage is even remotely correct.
My second part is: Could we improve upon the first sentence using some punctuation? Would a comma before 'so' make it correct if it is wrong? Or, should it be a semicolon before so and then a comma afterwards? I am writing them below:
He was sick, so he did not come. He was sick; so, he did not come.
Please give your valuable inputs, people.
PS: I would also like your comments on whether 'so' is a coordinator in itself. Or should it be 'and so'? I would like answers in formal English, as I need this information as a teacher of English and a writer.