## in that same region ##

"in that area" or "near Bethlehem"

## keeping watch over ##

"taking care of" or "guarding in order to keep them safe"

## flocks of sheep ##

"groups of sheep."

## at night ##

This could be translated as "after the sun had set and it was dark."

## an angel of the Lord ##

This could be translated as "an angel from the Lord" or "an angel who serves the Lord" or "an angel who was sent by the Lord."

## appeared to them ##

"came to them."