Are There Lost Alien Civilizations in Our Past?

Important Vocabulary Words From The Video


The sturdiest thing is the thing that can withstanding the most damage. The sturdiest materials are often the ones that are the most durable.

  • The sturdiest thing about the house was the walls.
  • The sturdiest thing about the tree was the trunk.

Fossilization is the process of turning something that was once alive into a dead object. Dead plants and animals can be fossilized, and so can rocks and other pieces of minerals.

  • The bones were fossilized after they died and were buried under the earth.
  • The rocks were fossilized after they were buried in the earth.

A sturdier object is one that is more resistant to damage. Something that is sturdier might be able to withstand a lot of abuse before it breaks.

  • The sturdier the material, the more expensive it is.
  • The sturdier the plastic, the more resistant it is to breaking.

To rot is to decay and to turn into something decomposable. When something rots, it starts to break down and lose its nutrients.

  • The vegetables in the garden are rotting because they are not getting enough sunlight.
  • The tree in the garden is rotting because the soil is not rich enough.

Cephalopods are a group of animals that include squid, octopuses, and cuttlefish. They are usually found in the ocean, but a few cephalopods live in freshwater.

  • Squid are cephalopods, and they are the most common type of cephalopod.
  • Octopuses are cephalopods, but they are usually considered to be a different kind of animal.
  • Cuttlefish are cephalopods, but they are the smallest type of cephalopod.

Harddrives are electronic storage devices that are used to store large amounts of data. They are often used to store music, movies, and pictures.

  • The computer doesn't have any harddrives installed, so you'll need to buy one.
  • The harddrive in the computer is full, so you'll need to delete some files.

To deplete something is to use it up or to exhaust it. When you deplete a resource, you are using it up faster than it can be replaced.

  • The resources in the park are being depleted by the number of people who are using it.
  • The workers are depleting the resources of the factory by working too hard.

Extinctions are events where a species of animal or plant goes extinct. This is a very serious issue because it means that the species is no longer alive and it can't be replaced.

  • The extinction of the dinosaurs was a very serious event.
  • The extinction of the dinosaurs was caused by a lot of different things, but one of the main reasons was the eruption of the volcano Mount St. Helens.