键盘增加功能如键盘按下，或是释放的英文

key.addlistener

• 键盘:    fingerboard; keybo ...
• 增加:    increase; raise; a ...
• 功能:    function
• 如:    in compliance with ...
• 按:    press; push down
• 下:    below; down; under ...
• 释放:    release; deliver; ...