Learn Dutch: We riskeren elkaars geld als we roekeloos gokken. - We risk each other's money when we gamble recklessly.

Just like in English, you can add an -s to the reciprocal pronoun elkaar (each other) to make it possessive: elkaars (each other's). It is placed directly before the noun. You could also say het geld van elkaar, but elkaars geld is much more common and concise.

Since this lesson is about the passive voice, how would we make the clause We riskeren elkaars geld passive?

Because elkaars geld is a direct object, it can easily become the subject of a standard passive sentence: Elkaars geld wordt (door ons) geriskeerd. It doesn't face the strict subject restrictions that indirect objects (dative passives) do, which often cannot become the subject without adding er or using a different verb.

Is roekeloos related to the English word "reckless"?

Yes, they are exact cognates! The Dutch suffix -loos means "-less". The stem roeke- comes from an old word meaning "care" or "attention" (related to the old English verb "to reck"). So just like "reckless", roekeloos literally means "careless", but it is specifically used to mean "reckless" or "rash".

Could we use the verb wagen instead of riskeren here?