"我家有四口人"用英语可以说成"There are four people in my family." 来源是指这句话是根据中文翻译而来。

"我的爸爸"用英语可以说成"my father"。来源是指这个词在英语中已经有了固定的意思，表示父亲。

"我的妈妈"用英语可以说成"my mother"。来源同上。

例句:

"My family consists of my father, my mother, my sister, and me." (我的家庭由我父亲、我母亲、我姐姐和我组成。)
"I have a happy family, my father, my mother, and my sister." (我有一个幸福的家庭，我爸爸，我妈妈和我妹妹。)
"I come from a family of four, my father, my mother, my brother and me." (我来自一个四口之家，我父亲，我母亲，我哥哥和我。)