What is your favorite machine? In My Favorite Machine: Concrete Mixers, young readers will learn all about concrete mixers. This book introduces kids to the different concrete mixers and the process used for making and transporting concrete. Sample Text: Cement mixed with sand or gravel and water makes concrete. These things are put into a drum that spins. The drum never stops spinning. If it did, the concrete would dry. Citește tot Restrânge