shoulder前用什么介词

前用介词on，例如：

1、Here it becomes very important to keep our head on shoulder.此时，保持头脑清醒时非常重要的。

2、He felt a tap on his shoulder and turned round.他觉得有人轻轻拍他的肩膀便转过身来。

3、The gentle touch of his hand on her shoulder made her jump.他的手轻轻地触了一下她肩膀便使她跳了起来。