💬 WHO and COMMAS in Relative Clauses Perhaps you’ve come across the following sentences: “My sister, who is a nurse, lives in Chicago.” “My sister who is a nurse lives in Chicago.” They look the same, so which one is correct? 🤔 Both ✅ They are both correct, but they send a different message. EXPLANATION 1️⃣ My sister, who is a nurse, lives in Chicago. - The speaker has one sister. - The information “who is a nurse” is extra information. - We already know who the speaker is talking about, so the clause is not necessary. 💡 That’s why we use commas. 2️⃣ My sister who is a nurse lives in Chicago. - The speaker has more than one sister. - The information “who is a nurse” is essential to identify which sister they mean. 💡 We cannot remove it, so there are no commas. Rule to remember: If the information is extra -> use commas. If the information is necessary -> no commas #relative clauses