The teacher said that there are/were seven continents in the world.

[Tan Elaine]

The teacher said, "There are seven continents in the world."

I was taught that in reported speech, it should be:

The teacher said that there are seven continents in the world.

Would it be correct if it is reported as 'The teacher said that there were seven continents in the world.'?

Thanks.

 

[Lynxear]

I would not say "The teacher said that there were seven continents in the world." unless that was what the teacher actually said. You are recording the speech not modifying it.

The use of "were" and "are" correct to use depending on context.

I would use "were" if I was being definite about the last time I looked at the situation and "are" if I was absolutely certain.

Are there five cookies on the table?

"There were five cookies there a few minutes ago." / "Yes, there are five cookies there."

 

[emsr2d2]

In reported speech, though, the direct question "Are there five cookies on the table?" would become "He/She asked if there were five cookies on the table". If the direct question were "Were there five cookies on the table?", it would become "He/She asked if there had been five cookies on the table."

"There are five continents" (spoken by a female) can become:

She said "There are five continents."
She said there were five continents.

I don't dispute that you will hear She said there are five continents​ and it's not wrong but it doesn't follow the usual reported speech backshift pattern.

(As always in my posts, these are BrE conventions.)

 

[Raymott]

If you always backshift in this situation, as I think I do, you will not get it wrong.

 

[Raymott]

I make no distinction for universal truths. "Galileo said the Earth revolved around the Sun."; "He said that water was H[SUB]2[/SUB]O."
Sure, it's not important, but if you're learning English, it's far easier to remember that you can always backshift. This means you don't have to think about it.