Please correct the following sentences.
This is the best book in the library.
I have to convert this sentence into comparative degree.
Shall I write it like-----
1. This book is better than any other book in the library.
2. This is better than any other book in the library.
My doubt is, Shall I write only "This" or "This book".
Make my doubts clear.
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Every one should read their book.
Every one should read his or her book.
The

First doubt ,shall I write "Every one" or "Everyone",because some where it is written like "Every one" and some where "Everyone".
The Second doubt about "their" and "his or her".
It is written that we can use "their" in Informal but "he or she" in Formal English.
My question is, shall I always use Formal, as I am a student.
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some boy ot the other has stolen my book.
This sentence is written in a English text book.
some time it is confusing. As "some boy" is indenfinite but same "ther other" definite. What are the correct rule for this.
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I don't like that ice-cream. I don't like this one too.
I think this sentence is not correct .This should be like-----
1. I don't like that ice-cream. I don't like this one.
2. I don't like that ice-cream. I don't like this one either.
Whic one is correct according to you?
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If I write a sentence like
1 .Ram is cleverer boy than any other boy in the class.
2. Ram is cleverer than any other boy in the class.
Which one is correct?
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John is the best of all other boys in the class.
is this right. Shall I use "other". Please explain it in detail.
Thanks .