Confusing Shifts Writers should keep the elements in a sentence consistent, avoiding any unnecessary changes in tense, voice mood, person number, and discourse. Such unnecessary changes, or shifts, may make reading difficult and obscure the sentence's meaning for the readerConfusing Shifts ❖Writers should keep the elements in a sentence consistent, avoiding any unnecessary changes in tense, voice, mood, person, number, and discourse. Such unnecessary changes, or "shifts," may make reading difficult and obscure the sentence's meaning for the reader