Answer :
The word that best fills the space in the sentence above is "key" forming the expression "keywords".
We can come up with this answer because:
- Whenever a word can help the reader find a specific element of the text, that word is called a keyword.
- Keywords can be of any grammatical class.
- In this case, we can say that these words can be nouns (such as a benefit or a ration), adjectives (a characteristic), adverbs, articles, or any other type of word.
- Keywords can guide the reader to something, including the main idea of the text.
In other words, we can say that a keyword is any word that refers to an important point in the text.
It is important to point out that the main idea of the text refers to the subject that the text is addressing.
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https://brainly.com/question/20841399?referrer=searchResults