sentence2_structure: The main function of the spleen<>is<>to filter the blood and remove unwanted red blood cells
sentence1: Spleen The spleen is an organ in the upper abdominal cavity that plays an important role in storing red blood cells, as well as filtering out old  red blood cells from the circulating blood supply.
sentence2: The main function of the spleen is to filter the blood and remove unwanted red blood cells.
question: The main function of this organ is to filter the blood and remove unwanted red blood cells?