Describe two diagrams There are two diagrams: the left one illustrates how the cement is made and the other one shows how the concrete is produced. There are six stages and two substances to make a bag of cement whilst it needs four ingredients to make concrete. To produce cement, limestone and clay are the main materials. In the first stage, put them together through a crusher to make them into powder. Then this powder is transmitted to a mixer and goes through a tube to reach a rotating heater where it will be rotated and heated. After heated, this hot powder is ground by a grinder to produce cement. In the final stage, the cement is packed into bags. The diagram on the right shows that concrete is a mixture of four ingredients. Each has different percentage to make concrete. Cement is made up 15% of the mixture, water accounts for 10%, sand constitutes 25%, and gravel (i.e. small stones) 50%. Put all of them into a rotating mixer then concrete is produced. (172 words) This is an essay for IELTS exam writing task 1. Hope someone could give me advice on what I did. Your help is greatly appreciated!