One way this arises very simply and commonly is the repetition of adjectives and adverbs for emphasis:

> We were going really, really fast!

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> I had a strange, strange dream last night.

On a different tack, there’s the interesting case of *What it is, is…*, discussed previously [here](https://english.stackexchange.com/questions/13056) and [here](https://english.stackexchange.com/questions/36683).