turn on:打开（电器之类的）
例如：Turn on the radio,please.
turn over:翻转
例外：If you turn the box over,you'll see some words at the bottom of it.
turn down:关小（电器之类的）声音
例如：Turn down the TV,please.Dad is sleeping now.
turn to:向某人求助
例如：He turn to his best friend for help. turn on:打开（电器之类的）
例如：Turn on the radio,please.
turn over:翻转
例外：If you turn the box over,you'll see some words at the bottom of it.
turn down:关小（电器之类的）声音
例如：Turn down the TV,please.Dad is sleeping now.
turn to:向某人求助
例如：He turn to his best friend for help.