"奶奶" (nǎi nai) 和 "爷爷" (yé ye) 在英语中分别是 "grandmother" 和 "grandfather"。
"Grandmother" 和 "grandfather" 是英语中表示祖母和祖父的常用词，它们来源于古英语 "grand" (大的、重要的) 和 "mother" / "father" (母亲/父亲)。
例句：
My grandmother makes the best cookies. (我奶奶做最好吃的饼干。)
I visit my grandfather every Sunday. (我每个星期天都会去看望我的爷爷。)
She is my father's mother, so she is my grandmother. (她是我父亲的母亲，所以她是我的奶奶。)
He is my mother's father, so he is my grandfather. (他是我母亲的父亲，所以他是我的爷爷。)