# When do you answer a question with “would be” instead of “is/are”?

Sometimes, I hear people answering questions with would be instead of is or are.

For example:

Who is that?

That would be our new teacher.

Why don't they say:

That is our new teacher?

What is the difference between the two answers?

In this case you use the 'would' for presumption or expectation.

That would be Jo calling. I'll answer it.

We saw a police helicopter overhead yesterday morning. Really? They would have been looking for those bank robbers.

"You have the conditional clear with those examples so on to presumption. That is like guessing. The phone rings, you expect or are waiting for Jo to call and you presume that it will be her. The chance is it may not be her.

Again as it is the police helicopter you guess it must be related to a police activity you are aware of, but again this is guessing, because you cannot know for sure. Any statement made about a certainty of which you cannot know is a presumption. That you may be right is not the point. At the time you make the statement you are presuming." - apex2000

You answer "That is our new teacher" when you know this to be true.

You answer "That would/will be our new teacher" when you are pretty sure (but not certain) that this is true.

• Do people use would/will be even though they know for certain? Maybe for sarcasm? – alex98 Jan 6 '16 at 14:27
• Definitely also used sarcastically. Someone asks 'who is that" (when it's obvious, everyone knows except them) - "That would be our new teacher (who else could it be you fool)". – Dan Jan 6 '16 at 14:33