diffusion is a process by which one culture or society borrows from another. 에서 밑줄 친 부분의 자세한 설명좀...

the more contact a group has with another group, the more likely it is that objects or ideas will be exchanged.
에서 밑줄 친 부분의 쓰임을 잘 모르겠어요, 알려주시면 정말 도움 많이 될 거 같아요.