Abbott's' two-cents' worth is correct. The only situation where it would be correct to say "I like pear" is if you are referring to flavours - for example, of ice cream or drinks. If you are talking about the fruits themselves, you have to use a plural form : "I like pears" or "I like mangoes". As "pear" and "mango" are countable nouns, it would be grammatically incorrect to use a singular form without a determiner. Someone referring to their favourite fruit by saying "I like pear" sounds like a two-year-old who hasn't learnt to talk properly yet - or an adult speaker of pidgin English with no understanding of basic grammar. If you want to refer to a specific individual piece of fruit, you would say, for example, "I like this pear" (which you are holding) or "I liked the pear which I ate this lunchtime.". Otherwise, to talk about a liking for a type of fruit in general terms, you have to use a plural. The same goes for any countable noun. For example, "I like that cat", "I like your cat" etc for a specific individual animal, or "I like cats" for the animals in general. You cannot use the word "cat" on its own in this situation.

There are different types of pairs. Therefore we would ask - Do you like pears?' - meaning ALL pears. I am not sure if there are different types of Mango - I think there is only one but I may be wrong. Therefore I would as - Do you like Mango? Hope this helps :-)

I gave you the correct answer here: https://www.italki.com/discussion/148016 Why ask again? The answer is the same no matter how many times you ask it.

When speaking of specific fruits, we always use the plural. We would never say "Do you like pear?" or "Do you like banana?" or "Do you like mango?" The correct answer is "Do you like pears?" (which would encompass all pears; if you wanted to be specific, you would name the type, e.g., "Do you like Anjou pears?"). And "I like mangoes" is correct, regardless of the type of mango. I see someone else answered differently, but that's my two cents.