plural/s

1.

I think. Yes, I'm sure. (It took me 20 seconds to write that sentence. Liat Y, your English must be improving, because your questions are getting harder. )

Technically I agree with mctag yet find Plurals difficult to say. It does not roll off the tongue readily.

In ordinary speech, I would, I am afraid, probably use the singular form.

Well, yet another country heard from . . . i also agree with McTutor, and i have no problem at all saying plurals, even though i am fairly certain i've never said it before.

And my avatar is much cuter than the avatars of McT and DP.

Thanks for the compliment. It is members, including you, who have helped me improve.

Without a shadow of a doubt, sentence (1) is the only correct one out of the two, although sentence (2) could be repaired as follows, although the result is excessively cumbersome:

I was taught that the plural of 'tomato' is 'tomatoes' and that the plural of 'potato' is 'potatoes'.