Jack as well as/ with/ along with/ together with his parents + is going to travel soon.
= 俗称“就远原则”
Jack's parents as well as/ with/ along with/ together with him(Jack) + are going to.
Jack and his parents + are going...
= Jack's parents and Jack + are going .A and B. 永远是“复数”+ 复数谓语动词.
这四句话的内容或意思是一样的,只是表达方式略有不同.