Sonnets could be defined by several characteristics: a) Iambic pentameter is used (5 pairs of syllables per line and the second one is stressed), b) 10 syllables are written in every line, c) they all have 14 lines. According to the different kind of sonnet, the rhyme structure could be different. As we can see, the structure is very rigid. On the other hand, free verse means that -free: there are no other rules than the ones the poet establish per every poem. Sometimes, the same poem can hold more than one way of dividing the verses: the speaker could go from long verses to a one syllable ones.
Sonnets belong to a very particular era of human history; due to that, there are some particular topics chosen by the poets who wrote or write those kinds of poems. Besides nowadays it is not very common, sonnets' writers usually take the same structure and the same topics the poets from the past did. Free verse poems discuss a bigger variety of topics, such as different forms. Maybe a poet who wants to discuss about today's topics may choose a free verse poem instead of a sonnet. Besides that, nowadays free verse poems are widespread, while sonnets are not.
The reason that you should use a free verse poem is because you can express yourself without having to rhyme or have rhythm on any of the subjects. While on sonnets you are expressing gratitude towards something that is either true or false. On the contrary they are both expressing something that is expressed with a feeling either false or true.
The reason you should use choose each of these forms is because it can be known to the others as something you want the world to know as an experienced or not. But the truth is you don't have to be in the world's pressure on what to write about. It is all about on how you feel as a person on that topic..
The expression, a chip off the old block means that people who resemble their parents in some way. For example, you could say <span>“Mark just won the same sailboat race his father won twenty years ago; he's a </span>chip off the old block<span>.”</span>
