Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to train a german shepherd to be a guard dog [title] Socialize your german shepherd when he is a puppy. [step] In order to have a well-trained guard dog, you will need to start socializing your german shepherd from a young age. Puppies are more receptive to new things until they are about 18 weeks old.

Ending1: You should let the puppy get to know you as a adult, then put him in his crate overnight. At 11 weeks, gradually introduce your dog to new situations. Ending2: Spending time with your german shepherd will allow you to bond with him and may keep him calm. Taking him outside and teaching him tricks can also be a great way to bond with him. Ending3: During this time, the things that they see, hear, and smell are less frightening. It is important to make sure that your german shepherd puppy is well-socialized during this time so that he will confident rather than anxious or fearful. Ending4: [substeps] Begin by using training sessions over the course of several weeks. Because the puppy's attachment to your dog is growing, you will need to find a balance between training and just walking him around.

Answer format: ending1/ending2/ending3/ending4