Final answer:
Tectonic plates are important because they shape Earth's surface, cause geologic phenomena, and recycle Earth's crust.
Step-by-step explanation:
Tectonic plates are important because they play a crucial role in shaping Earth's surface and geological features. The movement of these plates is responsible for a variety of geologic phenomena, including the formation of mountains, earthquakes, and volcanic activity. For example, when two plates collide, one plate may be forced beneath another in a process called subduction, which can lead to the formation of mountain ranges. Additionally, the process of plate tectonics helps to recycle Earth's crust, as new crust is formed at rift zones and old crust is destroyed at subduction zones.