Sonnets are poems that are written in iambic pentameter, meaning that they have five metrical feet, and have ussualy 14 lines, the main topic that they speak about is usually about love, so as sonnets are commonly written in iambic pentameter and have 14 lines, and are usually about love since they are born in the romantic period of literature, the only thing that is not true is that they are usually adressed to a man.