Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to look after your first puppy [title] Puppy proof your home. [step] Puppies are naturally curious animals, who like to chew up everything and always want to have a full stomach. Make sure to meet the requirements for a puppy-proof home.

Ending1: [substeps] Do not install or secure your dog in a cupboard or directly behind cabinets. Dogs can potentially chew through wood walls, wall liners, and floorboards. Ending2: [substeps] While puppies are unlikely to chew by themselves, be sure that you provide securely-contained areas for them to gnaw on. This might include walls, tall fences, or baseboards. Ending3: [substeps] Clean up any chemicals, and then put them in a cupboard. To puppies, chemicals like antifreeze can smell like candy, and they will lap it up eagerly, so make sure everything is put away properly. Ending4: Your puppy will jump out of your hands if it's not familiar with your home. You can make sure your home is secure by installing a fence, nailing boards to the walls, locking windows, and tying cords to doorways.

Answer format: ending1/ending2/ending3/ending4