I have no pens and no pencils.这里并列的是no pens和no pencils,整个句子可以说是肯定句,用and
I have no pens (or ) pencils.这里的并列是pens和pencils,前面有个no,.i have no是对后面所有的否定,所以用orAre you sure? 我的第一感觉也是这样，不知道对不对。I'm sure