"My sister's book"
Translation:मेरी बहन की किताब
OMG! I feel that the gender of inanimate objects will be a big challenge for me. Also, got some tips from: https://blogs.transparent.com/hindi/grammatical-gender-non-living-things/
A lingot from me for your help.
Interesting that the 's (after sister) is ki because the sentence before this one was "Raj is Julia's sister's son" and the 's after Julia was ki, but the 's after sister was kā. This is also an 's after the word sister but now its ki instead of kā. And yet they don't give us any info about why that's the way it is, which makes me wonder of its a mistake. And if it is not a mistake then an explanation would be in order!
By now you have likely figured this out, but I offer this in case other people come here looking for answers. किताब is a feminine noun, so when a postposition like का / की / के refers to it, it takes the feminine form की, regardless of the gender of the person doing the possessing (which coincidentally in this case is a feminine noun, i.e., sister). If the book belonged to Raj, it would still be राज की किताब. But if we are talking about Julia's son, son (बेटा) is masculine, so it must be जूलिया का बेटा. In english, we are used to things like possessive adjectives taking their gender from their subject (i.e., his book for a male owner or her book for a female owner) but in Hindi it is the opposite: the grammatical gender of the book determines the gender of the postposition or adjective that refers to it. Sorry if my Hindi isn't quite spelled correctly, but hopefully you get the idea.