Teachers please help me to correct my essay. Thank you very much

The figure describes the process that used to manufacture bricks

There are seven stages in the process, beginning with the work of clay digging. The clay is then shaped, treated to become finished products before delivered to customers.

At the beginning of the process, clay is dug from the ground. The clay is put through a metal grid, and it passes onto a roller where it is mixed with sand and water. After that, the clay can be shaped into bricks in two ways: either it is put in a mould, or a wire cutter is used.

At the fourth stage in the process, the clay bricks are placed in a drying oven for one to two days. Next, the bricks are heated in a kiln at a moderate temperature (200 - 900 degrees Celsius) and then at a high temperature (up to 1300 degrees), before spending two to three days in a cooling chamber. Finally, the finished bricks are packaged and delivered.