In some examples, a set of sentences is extracted from a digital document, and each sentence is scored using a respective informativeness measure and readability measure. Sentences in the set of sentences are selected based on the readability measures and informativeness measures. A low readability, high informativeness sentence is identified from the set of sentences. A concatenated sentence is generated by concatenating at least one contextual sentence with the low readability, high informativeness sentence, where the concatenated sentence has a higher readability than the low readability, high informativeness sentence.