Iambic pentameter is the most common type of meter used by Shakespeare in his sonnets. This is the type of meter that most resembles real speech in English, and this, together with the fact that Shakespeare preferred it, have made iambic pentameter the preferred type of meter in the English language. In the case of this sonnet, it contributes to its meaning in two ways. First, the meter places stress in certain important words and concepts, highlighting them to the readers. Second, the rhythm contributes to the development of intense emotional impact.