Subject + 落 + Complement
落 (luò) means "to fall," "to drop," or "to decline." It describes the downward movement of something, whether physical or metaphorical. It appears in many compound words and idioms, such as 落下 (to fall down) and 降落 (to land).
秋天到了,树叶纷纷落了下来。
qiūtiān dào le, shùyè fēnfēn luò le xiàlái.
Autumn has arrived, and the leaves are falling one after another.
雨点落在窗户上,发出轻轻的声响。
yǔdiǎn luò zài chuānghù shàng, fāchū qīngqīng de shēngxiǎng.
Raindrops fell on the window, making a soft sound.
夕阳慢慢落到了山的后面。
xīyáng mànmàn luò dào le shān de hòumiàn.
The setting sun slowly sank behind the mountain.