How do you say speak slower in greek?

There isn't a single perfect translation for "speak slower" in Greek, as the best way to phrase it depends on the context and your desired level of formality. Here are a few options:

* Μιλήστε πιο αργά (Miliste pio argá): This is a polite and common way to say "speak slower." It uses the polite form of "speak" (μιλήστε - miliste) and "more slowly" (πιο αργά - pio argá).

* Μιλάτε πιο αργά (Milate pio argá): This is similar to the above but uses the informal "speak" (μιλάτε - milate). Use this with people you know well.

* Μιλήστε πιο αργά, παρακαλώ (Miliste pio argá, parakaló): This adds "please" (παρακαλώ - parakaló) making it even more polite.

* Περισσότερο αργά, παρακαλώ (Perissotero argá, parakaló): This translates more literally to "More slowly, please". It's less common than the previous options but perfectly understandable.

The first option, Μιλήστε πιο αργά (Miliste pio argá), is generally the best and safest choice for most situations.