What two things should a reader use when making an inference?

Two things the reader can do are observation and background.

Explanation:

An inference is a form of opinion where the reader can notice clues in the text and make a guess basing on these clues. For the reader, it is important to read underlines and connect all the clues in one inference.

By the term observation, it is meant that the reader notices carefully all the clues or pieces of evidence in the text. This could help the reader to make a guess and draw a conclusion based on it.

By the term background, it is meant that the reader can use all of the familiar pieces of information to make an inference.

For example: In the book, the reader can see a man who is carrying a bag full of books, who always have a notebook and pen, and have a lot of papers in his bag. He often goes to the library to pick new books and he usually visits literature events. From all of these clues, the reader can make an inference that the man is the writer or professor who teaches literature.

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