The document discusses the second conditional, which is used to talk about unlikely or imaginary situations in the present or future. It is formed with "if" plus the past simple or past continuous for the conditional clause, followed by "would/could/might" plus the present infinitive for the main clause. Examples are given showing how the second conditional expresses things that are contrary to present facts and unlikely to happen, such as winning the lottery, having time to learn a language, or having the best grades to get a scholarship.