There are two situations in which I would use a comma before the word "and."
1) When three or more things are mentioned in a series: apples, bananas, and Oranges. This is called the series comma. It is used in American style more often than in UK style. But it is also correct to omit the series comma in US style.
2) In a compound sentence, which is two complete sentences joined by "and" (or another conjunction, such as "but" or "or"):
I went to visit my parents, and they were very happy to see me.
If the two sentences that make up the compound sentence are short and closely connected, the comma can be left out:
Stand up and state your name.
Depending on what the sentence is about you may use a comma before 'called';however, in some instances you may not be allowed to place a comma before the word called.
In a compound sentence, the comma would be placed before the word but.
It is usually appropriate to place a comma before "but." One should not use a comma after "but."
Say your sentence aloud. If you find you pause before the word 'therefore', you will probably want to insert a comma. If you do not pause, no comma is required. Use a comma when the sense requires it, not because you have a specific word in your sentence.
No, you don't use or put a comma before 'but' instead place it after it (but). Why? Simply because the word 'but' itself' acts as a comma, you pause when you get there. Never stop or pause the sentence until you get to the word itself as it acts out as a comma, even though there are some times where you can get a comma after it.
Not necessarily. Commas are a feature of sentence structure. There is no word or phrase in English that requires a comma.
Do NOT put a comma before subordinating conjunctions such as unless, if or because.
I do not use a comma before and after that word, therefore you will not see it in any sentence I have written.
No you don't.
It depends on the sentence.
The comma goes before the word "but." For example: I was going to spell the word "comma" right, but then I fell into a coma.