Include refers to something that is one part of another thing:
- The package holiday we bought included travel, accommodation, and breakfast.
(Travel, accommodation, and breakfast were part of the package.) - The price doesn’t include tax.
(Tax is not part of the price.) - I’d love to be included in the project.
(I’d love to be part of this project.)
Contain refers to things that are inside another thing:
- This book contains a collection of short stories.
(There is a collection of short stories inside this book.) - The gift box contained sweets and wine.
(There were sweets and wine in the box.) - Most takeaways contain too much salt.
(There is too much salt inside most takeaways.)
Look at this example:
- This book contains a collection of short stories including one by Oscar Wilde.
(There is a collection of short stories inside this book. One of these stories, that is, one part of the book is by Oscar Wilde.)
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