to ride (on a) horse

[Lenka]

Is it correct when I say e.g. "He rides on a horse." or "He's riding to the forest on his horse."? I guess the first example is incorrect, isn't it?

[Barb_D]

Usually, I would say simply "He is riding a horse."

I wouldn't say that "He rides on a horse" is incorrect, but that it's not natural.

Just like you might say "I saw him driving a convertible" instead of "I saw him driving in a convertible." It's not wrong, but it's just not often said.

[business writer, not teacher]

[BobK]

Is it correct when I say e.g. "He rides on a horse." or "He's riding to the forest on his horse."? I guess the first example is incorrect, isn't it?

No - it's fine. 'He rides on a horse' is OK. We usually drop the 'on' when specifying the sort of horse: 'He rides a black stallion' [specifying a habit] but the 'on' could be included there (especially if the verb's present continuous) - 'He usually rides a black stallion, but he's riding on a chestnut mare today'. [But don't take my word for it; other teachers may 'hear' this differently.]

If you mention the destination, you could omit the 'horse' altogether: 'He's riding to the forest' (you'd specify 'on a horse' if there was a range of possible mounts - 'on a horse' rather than 'on a mule/donkey/bicycle...).

b

[Anglika]

I would say that "He rides a horse" and certainly would not add "on" if saying someone is riding a different animal from usual. "Normally he rides a black stallion; today he is riding a chestnut mare".

"On a horse" is somewhat tautologous as "riding" implies being on the animal.

[Lenka]

OK, thank you for your replies! :)