Use to separate words or phrase.
a. Use a comma between each noun or adjective of quality in a list except the last noun or adjective;
Use ‘and’ before that last noun or adjective.
We bought tuna sandwiches, jelly and groundnuts for the picnic.
That kitten is a cuddly, playful and affectionate animal.
b. Use a comma between each phrase in a list except the last phrase;
Use ‘and’ before that last phrase.
I looked through the binoculars and saw a man struggling in the water, a speedboat moving towards him and a helicopter lowering a rope ladder.
c. Use a comma after an adverbial clause of time that begins a sentence
(Adverbial clause of time)
After we had finished dinner, we sat on the patio and played cards.
We sat on the patio and played cards after we had finished dinner.
d. Use a comma after a long phrase that begins a sentence
Desperate to get a ticket for the Thomas Cup Finals, James left his home at 5.30 a.m. so that he could be one of the first few people in the queue for tickets.
e. Use a comma before and after a clause or phrase that give extra information in a sentence.
David, my neighbor’s son, is doing a course in mechanical engineering.
We use a colon:
a. To introduce a list of items that add to what was said in the first part of the sentence
We bought four things from the jumble sale: a lamp stand, a rattan bookcase, a porcelain vase and a clock.
b. To introduce information that explains what was said or described in the first part of the sentence
I have a question to ask you: how do you complete the exercises so fast?
Finally, Mary came to a decision: she would resign from the firm.
We use a Semicolon (;)
a. To bring together two separate sentences which are connected in ideas to each other
Jenny has flu; her husband is not in the best of health too.
The company is well-known; its rubber products have won international awards.
b. To separate phrases in a list when the phrases have commas within them;
Use a semicolon with and before the last phrase
The managers who replied that they will speak at our function are form Ford, Smith and sons; Cooper and Richardson; and Caxton Incorporated.