your trousers are dirty,you must have them washed是否正确

问题描述:

your trousers are dirty,you must have them washed是否正确
麻烦附加讲解,OK?

Your trousers are dirty. You must have them washed. or
Your trousers are dirty and you must have them washed.
两个独立的句子之间不可用逗号.