Pets mimic our feelings. When we yell or quarrel, my boxer sits between me and the other person as if to protect me (from my family!). When I'm not thought well, they all lay around me and when we are laughing or having a upright time, my ChiChi's run around the house, panting and waging thier tail and they even start play-fighting with each other. So, I believe that freshly by showing them affection (rubbing thier ears and tummy), talking to them, etc, shows them you love them and they return that feeling ten-fold.
Answers: He will know if he's taken care of (well-fed, water available, walk when needed, etc.) The time you spend with him also accounts for a lot of it. If you praise him when he's worthy, play and cuddle with him, and overall just take the time to create him feel good, he will be happy to be near you. You'll see it in the way he greets you and the way he responds to you (wagging tail, kisses, etc.) Dogs may not give the name it love, but they know when it's there.
If he loves you, he must know you love him. Does he drop up and down when you come home even after you have only be gone a few minutes? If so, he loves you. I think they can tell.
some dogs will show you by like when you draw from home from work or running errands he will be jumping like he or she is prepared to play with you are showing that he missed you and he will be willing to play with you whether he knows you love him he will also listen to you better than a dog that feels abandoned by their owner
im not sure :/
some dogs can sense how you are feeling :D
so close to if you hug your dog or play with him he will know that you care in the region of him :)
Every night I go off a yellow sticky note for my dog : I love you! on the fridge door.
When my girl wakes up, the first piece she sees is the note, and that makes her extremely happy.