This book will be...,

[Silverobama]

Happy Holidays.

This book will be of great value to him in his study.

Is this italic sentence natural? I bought a book and want to give it to my cousin to help him with his English learning.

 

[gevalley]

snake game​

Happy Holidays.

This book will be of great value to him in his study.

Is this italic sentence natural? I bought a book and want to give it to my cousin to help him with his English learning.

This one feels a bit more personal and polite, which works especially well in a holiday context, right?

 

[teechar]

@gevalley : Please fix your profile info.

 

[Silverobama]

This book will be of great value to him in his study.

Is this sentence natural? "Study" also means "a room".

 

[teechar]

Is this sentence natural?

There's no need for the ending. You can say something like "This book will be useful to him" or "This book will help with his English learning".

"Study" also means "a room".

I don't think people would think of it that way in your sentence.

 

[Annabel Lee]

This book will be of great value to him in his study.

It would be more natural to use "in his studies":

This book will be of great use to him in his studies.​

The OED has the following to say about this plural usage of "studies": "In plural. The acquisition of knowledge or education by studying; esp. (frequently with possessive adjective) the pursuit of learning at a university, college, or the like; the work of a student." If you use "in his study," it would be better to add an "of"-phrase. For example:

This book will be of great use to him in his study of English.​