The girl asked the boy to help her walk the dog, and the boy said, I'm almost single dog ... Is that a refusal?

This is not necessarily understood as rejection, but it can be divided into several situations. The first situation is whether the relationship between this girl and that boy is very, very familiar. What the boy said to her was both provocative and probing. Maybe what he's trying to say is that you let me walk the dog. Look, I'm single, too! You walk me and I walk the puppy. Isn't that the best combination? So, if that's the case, girl, and you have a crush on him, he clearly expressed his crush on you. Is there any possibility of further development? It's up to you. What is the second possibility? If you don't know it very well, it may be that boys dislike walking dogs. His expression is an implicit rejection of you, and you can't force it any more. Just because you like puppies doesn't mean everyone likes puppies. Some people even get scared when they see dogs. Especially for boys, he can't tell you that he is afraid of dogs, can he? So it should be his wise choice to find a reason to reject you relative to the past.