Case 1

Look at the sentences below –

• • My friend John, is a good painter.
• • My friend, John is a good painter.

Which of these sentences has the commas placed correctly?

The answer is: neither of them!

Sentence 1 is grammatically incorrect.

In sentence 2 it is not clear whether the speaker is referring to John as his friend, or the person he is talking to as his friend. To understand this better, let us replace My friend with a name in sentence 2 – Tina, John is a good painter.

This would mean the speaker is addressing Tina (the friend) when speaking about John.

Now consider the sentences below. Both sentences are correct, but they do not convey the same thing.

• • My friend, John, is a good painter.
• • My friend John is a good painter.

“My friend, John, is a good painter. “

The use of commas in this sentence implies that I only have ONE friend – John- so his name is non-essential and could be left out. That is, I can say, "My friend is a good painter," and you would know that I mean John since he is the only friend I have.

“My friend John is a good painter. “

No commas imply I have more than one friend, so I need to specify John's name as essential information, ensuring that you understand that he is the friend I am referring to.

Case 2

Look at the below sentence –

• • My friend John, who is a better painter than me, can do the walls for your home.

Here the comma is not essential because the clause beginning with who, does not identify John. Note that even without the clause ‘who is a better painter than me’, the sentence is grammatically correct and conveys the message.

Case 3

While introducing someone, we use commas.

• • This is Jane, my sister.
• • The distinguished scientist, Mr. Stephen, of AKL University, will be addressing the audience tomorrow.

In the second sentence, the comma before and after the name indicates we are talking about a specific scientist of AKL University. The comma after the name also tells us that the information after the name is essential to identify the person.

As we see, the main instances where commas are necessary when referring to someone in a phrase are:

    ü  Where the sentence is focusing on a particular person.

    ü  While introducing a person.

    ü  Where the clause before/after the name is not essential.

Few more examples –

• • The mystery of the lost pencil has to be solved by Jim’s sister, Jane.
• • My cousin Tom, who won a free trip to Maldives, is leaving tomorrow.
• • I couldn’t complete the assignment alone, so I called my friend Sumy, who is faster and more knowledgeable.
• • Thankfully, Sumy could come and help me.
• • She was reading a book, A thousand splendid suns, which is quite a classic read.
• • A Thousand Splendid Suns, authored by Khaled Hosseini, is a fantastic novel.
• • This is Monica, my colleague.