Humans protect coasts using groins, breakwaters, and jetties to manage erosion and wave impact.
Groins are structures built perpendicular to the shore to interrupt longshore transport and trap sand, but they can lead to erosion downstream. Breakwaters act as barriers to protect coastlines from incoming waves, similar to barrier islands. Jetties are large structures at river mouths and harbors designed to stabilize the entrance and protect from wave action.
https://brainly.com/question/37204418