"Gas came into the kitchen."
Translation:Gas kam in die Küche.
Once again I am confused by the definite article. "into the kitchen" is a prepositional phrase; yet, for some reason, it is not translated "in der Küche" as the dative would seem to demand. I remember a Duolingo conversation that explains why, but the details of the conversation regarding why it is "in die Küche" escape me at the moment.
"In" is one of the two-way prepositions, that can have dative or accusative. They have accusative when it indicates a motion ('into') and dative when it means to stay at the same location, or in the same space. Here it is clearly motion, therefore accusative (die). The other example would be "Gas war in der Küche."