And he overthrew those cities: those cities refers to Sodom and Gomorrah. Overthrew, the same term as in verse 21, means “he destroyed.” In the light of the previous verse, some translations prefer to say “he burned up….”

And all the valley: that is, the valley or low-lying land where the cities are located. The same word is used in verse 17.

And all the inhabitants of the cities: translators may find it is clearer to link this statement to the destruction of the cities, and the final clause of the verse with all the valley. We may then translate “He destroyed those cities and their people [all the people who lived in them] and destroyed everything that grew in the entire valley.”

The lines of this verse follow the pattern a-b-a-b, in which a refers to the cities and b to the valley and land.

Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .