A Guideline between Mandarin and Japanese Pronunciation
For speakers of both Mandarin and Japanese and for linguistic enthusiasts, there is a general guideline regarding long vowels in Japanese Sino-Japanese vocabulary.
Examples
公園
English Translation: park
Mandarin Pronunciation: gong1yuan2
Japanese Pronunciation: こうえん (kōen)
警察
English Translation: police
Mandarin Pronunciation: jing3cha2
Japanese Pronunciation: けいさつ (kēsatsu)
上司
English Translation: boss
Mandarin Pronunciation: shang4si1
Japanese Pronunciation: じょうし (jōshi)
Notice that when there’s a -ng final in Mandarin, there’s usually a corresponding long vowel in Japanese.
Knowing this guideline can be helpful for Mandarin speakers who are studying Japanese, and vice versa.
Be aware that this guideline does not apply for all cases.
Counterexamples
強調
English Translation: emphasis
Mandarin Pronunciation: qiang2diao4
Japanese Pronunciation: きょうちょう (kyōchō)
迷信
English Translation: superstition
Mandarin Pronunciation: mi3xin4
Japanese Pronunciation: めいしん (mēshin)