The key to exercise solutions in chapter 12 - Grammar focus 1 for the textbook Cutting Edge Pre-Intermediate - Student's Book with authors Sarah Cunningham, Peter Moor and Araminta Crace from Pearson Education
Question
Who or what is the subject of sentences 3 and 4?
In sentence 3, who spends millions of dollars?
In sentence 4, who advertises the product?
In sentences 3 and 4, are we more interested in the action or the person / people who do the action?