Question One: No. In fact, the meaning is the opposite: "Readers accused the paper of using ignorant and offensive language" This means that the readers made accusations; in those accusations, the readers said the PAPER used ignorant and offensive language. "Readers accused the paper, using ignorant and offensive language" This means that the readers made accusations; in those accusations, the READERS used ignorant and offensive language. Question Two: You need to learn this combination: ACCUSE + object + OF + gerund. In other words, we 'accuse somebody of doing something'. For example, "He said that I had lied" = "He accused me of lying". Here's a tip: Nobody ever learns a language successfully by focusing on single words such as 'of'. You can waste years of your life memorising lists of words and still not be able to speak or understand English. The only way to learn a language properly is to focus on collocations, such as the collocation "ACCUSE + object + OF + gerund". Collocations are groups of words - often combinations of noun phrases, verbs and prepositions - which need to go together. Language is not a string of independent words: language is made up of combinations and patterns of words. If you want to make any progress at all in learning English, you need to focus on learning chunks of language, not individual words. I hope that helps.

It is a phrasal verb... One accuses someone OF doing something bad.