sentence2_structure: The human penis<>contains<>the urethra, as well as three cylinders of spongy erectile tissue
sentence1: The penis consists mainly of three cylindrical bodies of erectile tissue ( spongy tissue full of tiny blood vessels ) that run the length of the organ .
sentence2: The human penis contains the urethra, as well as three cylinders of spongy erectile tissue.
question: The human penis contains the urethra, as well as how many cylinders of spongy erectile tissue?