Learn Finnish: Kun me partioimme yövuorossa, meillä kaikilla on taskulamppu. - When we patrol on the night shift, we all have a flashlight.

In Finnish, when a pronoun is paired with a quantifier like kaikki (all), both words must inflect into the same case. Because the "have" structure requires the adessive case (meillä), the word for "all" must also take the adessive case, becoming kaikilla.

How would I change this sentence to say "both of us have a flashlight"?

You would use the exact same case agreement rule with the word molemmat (both). Since "we" takes the adessive case (meillä), "both" also takes the adessive, resulting in the phrase meillä molemmilla.

If the sentence is about "we all", why is the verb on in the singular rather than the plural ovat?

In a Finnish possession structure, the verb doesn't agree with the possessor (meillä kaikilla). It always defaults to the third-person singular (on) unless the thing being possessed is a plural word. Since they share a single singular concept here (taskulamppu), the verb remains on.

Why do we use the inessive case (-ssa) in yövuorossa instead of the adessive (-lla) like in the English "on the night shift"?