Вставьте артикль там, где необходимо. … main systems of … body have groups of organs working together to perform complex functions. … mouth, esophagus, stomach, small and large intestines are organs which compose … digestive system. there are some organs within … each system. … circulatory system is also called … cardiovascular system. the main function of … respiratory system is to convey … oxygen and to remove … carbon dioxide
