Read the passage and answer the question: Since a writer's main purpose is to explain things clearly, description is an important aid. To add liveliness to an essay, descriptive details are necessary to create a clear, unified impression of an object or a scene. As a technique in writing, description matches the kinds of details we see in vivid and effective photographs. Good descriptive writers help the reader to 'see' objects, scenes and even moods by means of language. — The most suitable title for the passage would be