Learn Italian: Hai troppa fretta, dovresti rallentare. - You are in too much of a hurry, you should slow down.

Dovresti is the present conditional form of dovere. While devi means "you must" or "you have to", dovresti translates to "you should". We use the conditional here because it is a polite suggestion or piece of advice, rather than a strict command.

Why is the sentence using "hai" (you have) instead of "sei" (you are) for "you are in a hurry"?

In Italian, being in a hurry is expressed with the verb avere (to have). The phrase is avere fretta (literally "to have hurry"). It works just like other Italian expressions of physical states or feelings you may have already learned, such as avere fame (to be hungry) or avere freddo (to be cold).

Why is it "troppa" with an 'a' at the end, rather than "troppo"?

Here, "too much" is describing the noun fretta (hurry), which is a feminine singular word. Because it's acting as an adjective modifying a noun, it has to match the noun's gender and number, so troppo changes to troppa. If it were describing an action instead, like "you work too much" (lavori troppo), it would not change.

Why is "rallentare" left in its infinitive (dictionary) form?