Buses will not exist any more and everyone will have his own car and his own computer too.

exist 是动词，意思是"存在、有"。这个词来自拉丁语 existere，由 ex-（"向外"）和 sistere（"站立"）组成，字面意思是"站出来"，引申为"存在"。 在句中使用了将来时态 will not exist，表示"将不会存在"。