Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to build a gable roof [title] Nail top plates to all the outside walls. [step] The top plates should consist of 2 boards of sufficient width to cover the tops of the walls. [title] Measure and cut ceiling joists from 2-by-4 lumber.

Ending1: [title] Dig an 18 " (51 cm) hole approximately 1/2 " deep on both sides of the ceiling joist. [step] Keep the top of this hole even, for stapling later. Ending2: [step] This will form the roof's bottom plate. [title] Trim all the pieces first with an 8' drill bit. Ending3: [step] You will attached these to each pair of rafters so they resist the outward pressure of the rafters on the walls. Install the ceiling joists onto the top plates so they span the structure from one long wall to the other. Ending4: [step] Ask their size, and then cut with your saw to the desired. [title] Add a roof plate to all the side walls as well.

Answer format: ending1/ending2/ending3/ending4