How do you place a gate in Sims 3?

To place a gate in The Sims 3, enter Build Mode and select the "Fences" category from the Build menu. Choose a fence type, then drag to create a fence section where you want the gate. After placing the fence, select the gate option from the same menu, and click on the section of the fence where you want the gate to appear. Adjust its position as needed, and your gate will be ready for use!