RobH_en_tn/gen/29/02.md

and, behold, three flocks of sheep were lying there by it

The word "behold" marks the beginning of another event in the larger story. Your language may have a way of doing this.

For out of that well

"For from that well." This phrase marks a change from the story to background information about how the shepherds watered the flocks. (See: rc://en/ta/man/translate/writing-background)

they would water

"the shepherds would water" or "those taking care of the sheep would water"

the well's mouth

Here "mouth" is a way of referring to an opening. Alternate translation: "the opening of the well" (See: rc://en/ta/man/translate/figs-idiom)