This is the 4968th most frequent Japanese word.
立ち去る
"To leave" or "to go away."
Here, '立ち去る' describes the act of the friend leaving, emphasizing departure.
私は友人が立ち去るのを見て、とても悲しかったです。
I was very sad watching my friend depart.
In this sentence, '立ち去る' is used to convey the necessity of leaving a place due to circumstances.
危険を感じたので、すぐにその区域から立ち去るべきだと思いました。
Feeling danger, I thought it necessary to leave the area immediately.
The word '立ち去った' is used as a past action meaning 'left' or 'departed', focusing on the act of leaving a location.