A good summary of an informational text must include all the details that the text contains about its subject. state, in the student’s own words, only the most important ideas. evaluate whether the text’s author covered the subject matter well. use phrases and seA good summary of an informational text must include all the details that the text contains about its subject. state, in the student’s own words, only the most important ideas. evaluate whether the text’s author covered the subject matter well. use phrases and sentences taken directly from the original author. ntences taken directly from the original author.