Complex sentence: Mao was concerned about the speed of capital accumulation and the production of the means of production and of the opinion that China was on the right course of balancing heavy industry on one hand, and light industry and agriculture on the other.
Split into simpler sentences: Mao was concerned about the speed of capital accumulation and the production of the means of production. He was of the opinion that China was on the right course of balancing heavy industry on one hand, and light industry and agriculture on the other.