Direct object is the receiver of action withing a sentence.A direct object will follow a transitive verb [a type of action verb].
subject + verb + what? or who? = direct object
Mike and Laura played soccer with many difficulties.
Mike, Laura = subjects; played = verb. Mike and Laura played what? Soccer = direct object.
Direct objects can also follow verbals—infinitives, gerunds, and participles.
verbal + what? or who? = direct object
To see magnified blood cells, Gus squinted into the microscope on the lab table.
To see = infinitive. To see what? Blood cells = direct object.
He left her all his money.
My friend sold me his book.