Left my first real code review comments on a senior engineer's PR and rewrote the sentence four times

Two years in, finally got added as a reviewer on someone more senior than me. Found a real edge case that would've broken on empty input, but spent twenty minutes wording the comment so it didn't sound like I was correcting them. They just said good catch and fixed it in five minutes. Nobody warns you that giving feedback up the seniority ladder is its own skill you have to build separately from writing code.