Hi Jandrisista, you have asked a very interesting question. I would like to answer to your question. In Hindi, there are seven cases and one of them is called oblique case. . It is the most important case in Hindi. Although we do not have this case in English. First thing we need to know is what is oblique case? when a noun is followed by a postposition . Noun turns into oblique and there is a need to make some changes in sound. for example, eye is Aankh, plural of Aankh is Aankhen and When plural feminine noun (aankhen) is followed by a postposition, in that case en is changed into on and It becomes aankhon. Here is another example Book is Kitaab (singular) Books is Kitaaben (Plural) In the books is Kitaabon me (Plural oblique) In the last example , Kitaaben is chnaged into Kitaabon because Kitaaben is followed by word me (in) which is a postpostion.

aankh is singular - eye आंख aankhei would be plural - eyes आंखें aanko आंखों would be plural with a postpositions for example me में, ko को, par पर

Aankho is the plural form of aankh. Such as eyes and eye. If there are more than 1 eye then we will call it aankho means eyes instead of aankh.

when we talk about one eye only its aankh but in general we talk about both eyes so we say ankhe/ ankhe as per sentence demand. as we say look at my eyes ( meri ankho mai dekho).

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