since; as; this being the case
既 · 9 strokes
Depicts a person, who is full, turning away (旡) from a container of food (皀). Based on the original meaning "finish eating". The meaning later shifted to "complete" and "already".
然 · 12 strokes
Phonosemantic compound. 灬 represents the meaning and 肰 represents the sound. Based on the original meaning "burn", now written as 燃. The current meaning is a phonetic loan.