~がする — to sense/feel (used with sensory experiences like smell, sound, taste)
This expression is used to describe sensory perceptions. The particle marks what is being sensed, such as a smell, sound, taste, or feeling. It combines with nouns related to the five senses.
This room has a strange smell.
この — this部屋は — room (topic marker)変な — strange, weirdにおいが — smell (subject marker)する — to do, senseBecome a Makoto+ member for bonus content: www.MakotoPlus.com