"画等高线" can be translated as "draw contour lines" in English.
In the context of cartography, geography, or engineering drawings, "等高线" (děnggāoxiàn) refers to lines on a map or chart that connect points of equal elevation above a specified level, usually sea level. "画" (huà) means "to draw" or "to paint." So, combining these two parts, we get "draw contour lines" as the appropriate English translation.