The document discusses the proper uses of the words "like" and "as" in English. It explains that "like" is used as a preposition followed by a noun, while "as" is a conjunction used before a clause with a verb. Some common phrases with "as" are also outlined, such as "as you know". The document provides examples of when to use each word and cautions that "like" and "as" can change the meaning in similar sentences. Exercises are included to reinforce the differences between "like" and "as".