Gender-neutral subject pronoun, grammatically equivalent to the gendered pronouns he and she
A drop.
To strain, as milk; filter.
To drop, as water; trickle.
To fall, as in a swoon; faint.
To sift.
To sink; fall; drop.
A single person, previously mentioned, but typically not if previously named and identified as male or female, especially if of unknown or (since 21st century) non-binary gender.
There (especially as an expletive subject of be).
People; some people; people in general; someone, excluding the speaker.
A group of entities previously mentioned.
Their.
The, those.