Short answer question

#23.

Briefly explain the four stages of making an expendable mold casting.

My answer:

There are four stages in making an expendable mold casting. The first is making the pattern. In the second step, the pattern is surrounded with sand or plaster. During the third step, the liquid material is introduced and allowed to solidify. Lastly, the mold is broken up and the casting is removed.

I don't know how to explain it in details. Can I get some help please ?