I have some questions about the English articles.?

I'm learning the English articles. I think that the definite article “the” isn't used at which it has to be used in the following three sentences extracted from my books. ①“All 26 people on board the plane were killed." Why isn't “all the 26 people”correct in this sentence? ②The trail of death... show more I'm learning the English articles.

I think that the definite article “the” isn't used at which it has to be used in the following three sentences extracted from my books.

①“All 26 people on board the plane were killed."

Why isn't “all the 26 people”correct in this sentence?

②The trail of death touched all corners of Africa.

Why isn't “all the corners” correct in this sentence?

③For convenience of reference, there are summaries at the beginning of all chapters, and a full index at the end of the book.

This sentence is extracted from “Meaning and the English Verb: Edition 3”.

Why isn't “all the chapters” correct in this sentence?
Update: My English is very poor,sorry.

the definite article “the” isn't used at which it has to be used → the definite article “the” which has to be used isn't used
2 answers 2