Hindi

Spoken at everyday register, Hindi and Urdu are mutually intelligible — most linguists treat them as one language (Hindustani) with two literary standards. The split shows up in script (Devanagari vs Perso-Arabic), in formal vocabulary (Sanskritic for Hindi, Persian and Arabic for Urdu), and in cultural framing rather than core grammar.

Devanagari, an abugida where each consonant carries an inherent 'a' vowel, modified by attached vowel marks. The script is largely phonemic — what you see is what you say — which makes reading easier to learn than the writing systems of English or Mandarin.

Yes, two: masculine and feminine. Every noun is one or the other, and adjectives, verbs, and some postpositions agree. There are patterns (most nouns ending in -ā are masculine, most ending in -ī are feminine) but exceptions exist and the gender of borrowed nouns is rarely predictable.

In the past tense of transitive verbs, the subject takes the postposition ne and the verb agrees with the object instead of the subject. This split-ergative pattern shows up in Hindi, Urdu, Punjabi, Marathi, and several other Indo-Aryan languages but not in English or any European language.

The script is straightforward once you commit a week or two to it. The grammar takes longer: postpositions instead of prepositions, SOV word order, gender agreement on verbs, and the ergative past have no English parallels. But Hindi is regularly spelled, mostly pro-drop, and rich in cognates with English via Sanskrit.