Comparing "bang" and "bangzhu"
帮 and 帮助 both are verbs that mean to help or to assist. 帮 is used in informal settings, whereas 帮助 is used in informal or formal settings. While both words can often be used interchangeably, there are set patterns and phrases can only use 帮 or 帮助.
只有帮可以这么使用“帮一帮我”, “帮帮我“
帮助的固定搭配“互相帮助”