21. Without the ability to think critically, to defend their ideas and understand the ideas of others, they cannot fully participate in our democracy.

【分析】簡單句。句首介詞短語without…others作條件狀語，其中the ability后跟不定式短語to think critically, to defend their ideas and understand the ideas of others作其后置定語；句子的主語為they,謂語為cannot fully participate in，賓語為 our democracy。
【譯文】如果沒有能力進行批判性思維，維護自己的觀點，并理解他人的觀點，他們就不能充分地參與到我們的民主政治中來。

22. "Intellect is resented as a form of power or privilege," writes historian and professor Richard Hofstadter in Anti-Intellectualism in American Life, a Pulitzer-Prize winning book on the roots of anti-intellectualism in US politics, religion, and education.

【分析】句子主干為一個完全倒裝句。謂語writes放在主語historian and professor Richard Hofstadter 之前；賓語為直接引語。in Anti-Intellectualism in American Life作狀語，斜體部分為書名，后面a Pulitzer-Prize inning book...是其同位語。
【譯文】“才智被人們看作一種權力或特權而遭到憎惡，”歷史學家理查德·霍夫斯塔特教授在他的《美國社會中的反才智主義》—書中這樣寫道。這本曾獲普利策獎的書探討了美國政治、宗教和教育中的反才智主義的根源。
【點撥】本句中on是“關于，以…為主題”的意思。