to leave it to (someone); to let (someone do as they please); to be up to

(bound form) cause; reason; source

Used to introduce the person or group responsible for an action, meaning "by" or "it is up to... to..."

due to; because of; as a result of

from; starting at a place or time

via; through; by way of; to pass through

to follow; to obey; to adhere to

a Chinese surname

(literary) means; opportunity; way (to do something)