All expository writing can be divided into these three major patterns of composition?

You are close! While expository writing often uses these patterns, they are not the only ones. Here's a breakdown:

The three major patterns of composition commonly used in expository writing are:

1. Cause and Effect: This pattern explains how one event or situation leads to another. It answers the "why" question.

* Example: Explaining the causes of climate change and its effects.

2. Compare and Contrast: This pattern examines the similarities and differences between two or more things. It helps readers understand the relationships between them.

* Example: Comparing and contrasting the benefits of electric cars versus gasoline cars.

3. Process Analysis: This pattern describes the steps involved in a particular procedure or activity. It provides clear instructions or explanations.

* Example: Explaining the process of writing a research paper.

However, these are not the only patterns. Other common patterns in expository writing include:

* Definition: This pattern explains the meaning of a term, concept, or idea.

* Example: Defining the term "artificial intelligence."

* Classification: This pattern divides a topic into categories and examines each category in detail.

* Example: Classifying different types of governments.

* Problem and Solution: This pattern identifies a problem and presents possible solutions.

* Example: Analyzing the problem of pollution and proposing solutions.

Remember: Expository writing can also use a combination of these patterns, depending on the topic and the author's purpose. The key is to use a clear structure and organization to effectively convey information to the reader.