Auto-complete formula?

I'm sure that this is a really basic question. When I start typing a formula, possible formulas appear below it. How do I select one of these to auto-complete with the keyboard?

Thanks,
Rob

You can use the Down arrow key and then Tab.

And, no, that's not a really basic question.

Perfect! Thanks. Learning Excel is a process. Sorry for asking stupid questions. Thanks for answering them

You're welcome. And there are no stupid questions. (Actually there are, but that wasn't one of them).

I'll try (I'm sure unsuccessfully) not to ask the stupid questions