You can watch over it. But just watching .. It's like having a cop sit in a car to watch the bank, but if robbers come he "watches" them rob the bank. Watching over/guarding implies active measures, watching implies your seeing what's happening. (Yeah you could use I'll watch your child, but that's because colloquially we know what that means. But literally, it seems too vague.) That's just my ten "pund" note worth. https://youtu.be/xG6oCrtef5A (link goes to Mitchell & Webb's "ten pund" money tv clip)
as NoamSteiner mentioned before, the common use of "to save money" is לחסוך\חוסך and not לשמור/שומר. other uses I can come up with are 1. שומר- guard 2. לשמור חניה/לשמור מקום- to save a parking space or to save a spot somewhere 3. שומר as in "keep" like in שומר סוד- keeps a secret.
to guard; to safeguard; to watch, to supervise; to keep, to maintain; to observe (rules) (from Morfix: https://www.morfix.co.il/en/%D7%A9%D7%95%D7%9E%D7%A8)
Thanks for saving me the trouble of finding the link to all the meanings of לשמור! Since there is no context to this sentence, all of them should apply. (I'm sure the sentence writer had a context in mind, but s/he didn't share it with us.) I just got dinged for using the "guard" meaning for it. This called for a lingot, and I gave you one.
Thank you. That makes a lot of sense. Saving something for later is keeping holding of it whereas "save" in the sense of rescuing is a semantically distinct concept.
Ha! Archaic is good! I know this a Modern Hebrew course but another one of my objectives to understand the siddur a bit better too. I have a printed textbook for that.