Somebody is knocking on the door outside. The person inside the house says, "Who is it?"
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Why does he say 'Who is it?"
What about "Who are you?" Can't we use "Who are you?" Do you have any difference between the two sentences?
"Who is it?" is just a common expression. If the person inside says "Who are you?" it comes across as a bit insulting. This is one of those idiomatic things that really defies explanation!
The person inside the house says "Who is it?" as a polite and respectful way of asking the identity of the person at the door. This phrase is commonly used when someone wants to know who is at the door without sounding confrontational or accusatory.
On the other hand, "Who are you?" can also be used to ask for someone's identity, but it may sound more direct and assertive. This question might be used in a situation where the person inside the house wants to know who is at the door in a more urgent or concerned manner.
The difference between the two sentences lies in the tone and intent. "Who is it?" is softer and more polite, while "Who are you?" tends to be more direct and possibly a little less polite. The choice of which phrase to use can depend on the specific situation and the relationship between the people involved.
If you want to know who is at your door, you can use either phrase depending on the level of urgency or formality you want to convey.