This is a tutorial segment of Double comparatives of English Grammar. In this lesson, the instructor is explaining about how to express a cause and an effect in a easier way with examples. She says that it's the relationship where one thing makes a change on another or one factor say for example sunshine, produce a result in another by making us to feel happy. Comparative forms are used to express a cause and effect. Words like brighter, happier are examples for that. For example, in the sentence, The brighter the sun, the happier I feel. Here, the cause is "brighter" and effect is "happier".