and therefore
Very common
Conjunction
Type:Coordinating
Subtype:Copulative
Mood:None
Punctuation:A comma is often used before a proto when it links clauses.
Examples
It is raining, and therefore I am not going out.
It is late, and therefore I am sleeping at home.
I have time, and therefore I will help.
I am sick, and therefore I will stay home.
It is expensive, and therefore I will not buy a car.