The dog made a long "ah ah" sound.

Some dogs will make "ahhh" when they are depressed and sad. My old dog Huahua just got back from his mother. Every night when we sleep, it runs to the balcony and barks. I am very sad because I left my mother and missed her. Your dog can't see you and plays with you because you left it at home. It also makes such a "ah-ah" sound, which proves that the dog loves you and doesn't want to be separated from you.