如果英语句子是第三人称单数,句子中需要用到“然后（then）”来连接,那么then后面的动词要加“s”或“es

then 和 and 不一样.
then后面的动词是否要加“s”或“es,要看then下面的人称.
但很少有加“s”或“es的情形.
It costs $20,and then there's the sales tax to pay.
If traffic is heavy,then allow extra time.