Is there any guidelines/rules I can follow on the pronunciation of शहर? In the sentence it sounds more like Cheher instead of Chahar. Same goes for बहन (sister) which sounds like behen instead of bahan?
Words with ह in the middle or the end are exceptions to phonetic pronunciation in Hindi. When the ह is sandwiched between अ on either side (For example, in शहर it is between the अ attached to श and the one attached to ह), both those अs are pronounced as 'e'. The 'e' sound is similar to the 'e' in 'bed'. This is a quirk of spoken Hindi and this sound is formally absent in written Hindi though Devanagari represents it as ऎ (shorter version of ए) for use in other Indic languages.
You can see this pronunciation in many words like बहन(sister), कहना(to say), पहन(wear) etc. If the ह is at the end of the word where the last अ would not normally be pronounced (like छह-six), you leave out the last 'e' sound too. So, छह is pronounced 'cheh'.
There was a good and detailed post on this forum about how the letter ह often messes with phonetic pronunciation in Hindi but I'm unable to find it at the moment.
Why is "Which town is there?" not accepted? It´s hard to believe this is really wrong.
I know what the right answer is, but I don't know what this connunicates, since that's not an English sentence.