1. This book is worth reading.

Question

2. It is worth to read this book.
3. This book is worth to read.
4. It is worth while to read this book.
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Which ones are grammatical? Do we have other patterns using 'worth'?

Answer 1

1. This book is worth reading. OK
2. It is worth it to read this book. note the correction
3. This book is worth to read. not OK
4. It is worthwhile to read this book. note the spelling correction