usher
n.引座员;招待员;门房;助理教员
An usher is a person who shows people where to sit, for example at a wedding or at a concert.
v.引领,招待;做招待员;宣告
If you usher someone somewhere, you show them where they should go, often by going with them.
而guide
vt.引路;指导;操纵;影响
If you guide someone around a city, museum, or building, you show it to them and explain points of interest.
n.指导者;向导;导游;有指导意义的事物
A guide is someone who shows people the way to a place in a difficult or dangerous region.
注意看英文解释,是柯林斯高阶英汉词典的解释。所以说,用作引导的时候usher一般指将某人领到某一个位置,而guide是有向导的含义,带有接待、解释意义。