pronunciation of ている


(The question was asked
[here](https://japanese.stackexchange.com/questions/43507/%E3%81%A6%E3%81%84%E3%82%8B-pronunciation-
internalization) but the answers didn't really address what I am about to
ask.) One rule about long vowels is that the long vowel for え段 is written え段 +
い. For instance けいじどうしゃ is pronounced as ケージドーシャ, not ke-i-ji-do-u-sha.

What about the ている pattern for verbs, as in 知っている? Is it te-i-ru or te-e-ru?




The rule you mentioned does not apply across word boundaries. For example,
海外へ行きます is pronounced like 海外エイキマス, not like 海外エーキマス, because へ is a particle
and 行く is a verb. Likewise, 知っている is made of three words (知っ + て + いる, where
[this て is a particle](https://japanese.stackexchange.com/q/36310/5010)), so
it's not pronounced like シッテール. In addition, in colloquial speech, 知っている can
be safely shortened to 知ってる, so there is no point of elongating て.

(Compound nouns like ため息 and さざれ石 tend to be pronounced like タメイキ and サザレイシ,
too, but some people may pronounce them like タメーキ and サザレーシ.)




The rule you mentioned does not apply across word boundaries. For example,
海外へ行きます is pronounced like 海外エイキマス, not like 海外エーキマス, because へ is a particle
and 行く is a verb. Likewise, 知っている is made of three words (知っ + て + いる, where
[this て is a particle](https://japanese.stackexchange.com/q/36310/5010)), so
it's not pronounced like シッテール. In addition, in colloquial speech, 知っている can
be safely shortened to 知ってる, so there is no point of elongating て.

(Compound nouns like ため息 and さざれ石 tend to be pronounced like タメイキ and サザレイシ,
too, but some people may pronounce them like タメーキ and サザレーシ.)

