Islam tells us that a person in the grave is either enjoying a peaceful stay or going through punishments depending on his/her deeds. However, many people doubt this fact. This is due to the reason that when a grave is dug, we do not see any fire burning people or gigantic snakes biting dead bodies. All we see are bones mixed with soil. Well, then where is the punishment or peace? Whether we can see it or not, the promise of Allah is true. Allah gave us many things to understand things better. He tells us that there are signs in His creations for those who think. To understand this particular issue (grave) better, we can examine our dreams. Say, a person is sleeping right beside you. He is seeing a dream where some people are trying to kill him. They catch him and starts beating him. Finally, they take out a gun and shoots him. You are sitting beside this sleeping individual, but you do not see any of these things. However, he is experiencing all these things, it's just you cannot see. The same way, that individual in the grave is going through all the things that are promised by Allah, it's just we cannot see.
There are important purposes in dreams for someone who reflects. Such a person thinks about how "realistic" the dreams are that he sees while asleep, which in that way are no different in their realism from the moment he awakes. For instance, despite one person's body lying on the bed, in dream he went on business trips, met new people, and had lunch while listening to music. He enjoyed the taste of his meal, danced to the music, became excited because of the incidents that happened, became happy and unhappy, was afraid and felt tired. He could even have driven a vehicle that he had not previously driven until that day and did not even know how to drive.
So, you can experience, see, touch, hear and taste things that are not only real but also things that are unreal.