The Curious Case of Ha
In Hindustani, the letter ह /ɦə/ appearing after certain vowels, alters their pronunciation. Those being अ /ə/ a and उ /ʊ/ u: 1. The a tends to get closer to the ai /ɛː/ sound but it is still a short vowel [ɛ]. For example, कह is pronounced [kɛɦ]. If the h comes between two a's, both of them see this change. For example, लहर is pronounced [lɛɦɛɾ]. 2. The u, on the other hand, becomes a short au /ɔː/, i.e. [ɔ]. For, example, the word मुहब्बत is pronounced [mɔɦɔbːət̪]. 3. Though it is not exactly the case with इ /ɪ/ i, in some words, such as सेहत which is spelt in Urdu as Sihat, there is an [e] sound. Now, this is why you might want to avoid spellings like मोहब्बत and शेहर and instead use spellings like मुहब्बत and शहर so that you don't pronounce them wrong. Some of these spellings have found their way into the standard as alternatives of the original spelling, such as मोहब्बत and बेहतर (originally बहतर) while other spellings have completely replaced their original counterparts such as चेहरा, मेहरबान, मेहनत, etc.