however作为转折 用必须要和后面的句子之间加 , 请详解

无论用在句首,句中,however 后面一定要加逗号.比如:We will go to Beijing next week.However,if the weather there is too cold,we may have to change our plan.
A great majority of people are,however,still not rich.

扩展阅读：but和however用法区别 ... however表转折还是递进 ... but和however 转折用法 ... however放句首的用法 ... however不能和什么连用 ... however用法及含义 ... however的用法和位置 ... however不能连接两个句子 ... however引导的是什么从句 ...