Thomas Paine · 1737
Heavy going at CET-4 level. Not unreadable — just not readable the look-every-word-up way.
Coverage = the share of words in the text you already know. The research gives two lines: 98% before independent fluent reading is realistic, 95% for the instructional level that needs support (Hu & Nation, 2000). Proper nouns are not counted as unknown — recognising that it is a name is enough; this book has 178 of them.
Advanced — read it with glosses. 21,933 words in total; at 150 words a minute for a non-native reader, about 2 h 26 min to finish. Average sentence length 30.1 words — on the long side, so the load comes from sentence structure as much as from vocabulary. Reaching 95% coverage on this book (the floor for readability) takes roughly 19,750 word families.
The opening of Common Sense, word for word. Tap any word you don't know and its meaning here appears beside it — no sign-up, tap as often as you like.
Perhaps the sentiments contained in the following pages, are not yet sufficiently fashionable to procure them general favor; a long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom. But the tumult soon subsides. Time makes more converts than reason.
As a long and violent abuse of power, is generally the Means of calling the right of it in question (and in Matters too which might never have been thought of, had not the Sufferers been aggravated into the inquiry) and as the King of England hath undertaken in his own Right, to support the Parliament in what he calls Theirs, and as the good people of this country are grievously oppressed by the combination, they have an undoubted privilege to inquire into the pretensions of both, and equally to reject the usurpation of either.
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These are already built, and closest in difficulty to Common Sense.
Ordered by unknown words per 100. Lower reads easier; to step up a level, pick a higher number.
Computed by Readii from the public-domain text (updated 2026-10-21), not estimated by hand. The Readii reading level is our own scale, anchored on unknown-word density; it is not the same system as Lexile or AR and does not convert directly. Unknown words are measured against the CET-4 ∪ Gaokao lists, so this is difficulty for a Chinese-speaking learner, not a native-child reading level.