Correct speech, mother tongue and water

For a sentence to be correct, words are used in their place and in a suitable form. Sometimes a word lands in the wrong place and the meaning is spoiled. For example: «Men maktabni kitob o‘qiyman» is wrong. The right form: «Men maktabda kitob o‘qiyman» (I read a book at school). We read a wrong sentence, find which word is incorrect and correct it. The textbook has a task of correcting wrong sentences in a child’s story.