How to pronounce 繁栄 han'ei? How to pronounce han'ei? Is there a glottal stop between the two syllables? Is it //haɴʔeː//, //haɴeː//, //haŋʔeː// or //haŋeː//?

and , , ... are pronounced //haɴeː// without glottal stop and as //ɴ//.

The combination //ɴ// + vowel is difficult to pronounce, so in some cases, such as , orthography has been adapted to allow for easier pronunciation (although might still be considered a valid pronunciation). Usually though a word has only a single valid spelling, which sometimes may help to distinguish homophones, e.g. and .

This phenomenon is called and usually occurs with //ɴ// + //aou//, although the Wikipedia page also gives examples for > .

I guess one should also mention that in the case of //ɴ// + //i//, there is , which is more often than not pronounced ...

In any case, //ɴ// + //aiueo// sometimes calls for attention to detail, but putting exceptions aside, + is pronounced //ɴ// + //aiueo//. In the case of //ɴe// the phonetic realization usually exhibits some palatalization as in [[haɴʲe:]] or nasalization as in [[hãːeː]] (see comments below).