It can also occur within a clause, sentence, or section of a poem. Ceasuras are used because they help create emphasis or tension within a poem. Without a caesura, an idea might seem too long or complicated to be understood easily by readers. The use of punctuation allows the poet to break the language up into easy-to-read sections by inserting natural breaks in speech or thought. There are two main types of caesuras: internal and external. An internal caesura occurs within a single unit of language, such as a clause or sentence. Now, instead of saying just "I like green apples," I would also like to tell you something else - maybe even give you an argument for why green apples are best after all! This addition makes my meaning clear without repeating myself too much.