胸鎖 きょうさ乳突 にゅうとつ すじじゃなかったです
kyōsa nyū totsusujijanakattadesu

Noun
Desu Copula

The polite, past negative form of 胸鎖乳突筋

1. Wasn't the sternocleidomastoid muscle.

Past/Perfective
Negative
Polite
Casual Register