alternation by turns in turn rotation take turns turn turn and turn about
轮流;
drop dropt lay down let down plop put down set down stick down vail
放下;
drop dropt lay down let down plop put down set down stick down vail
放下;
devolution in file in turn priority take turns turn and turn about
依次;
disassembly knock down strip take down take-down tear down teardown
拆卸;