" I wouldn't drop "on". "check on" seems more idiomatic to me in that sentence. "to check ( usually something)" seems more like determining its accuracy or correctness, with the implication of keeping it in control.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
park sang joonI think here in "check on" I can drop "on."I wouldn't drop "on". "check on" seems more idiomatic to me in that sentence.