W. E. B. Du Bois · 1868
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 636 of them.
Advanced — read it with glosses. 69,049 words in total; at 150 words a minute for a non-native reader, about 7 h 40 min to finish. Average sentence length 25.5 words — on the long side, so the load comes from sentence structure as much as from vocabulary. This book is heavy on rare, archaic and invented words: even 25,000 high-frequency word families will not reach 95% coverage — its difficulty is not in the common vocabulary.
The opening of The Souls of Black Folk, 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.
Between me and the other world there is ever an unasked question: unasked by some through feelings of delicacy; by others through the difficulty of rightly framing it. All, nevertheless, flutter round it. They approach me in a half-hesitant sort of way, eye me curiously or compassionately, and then, instead of saying directly, How does it feel to be a problem? they say, I know an excellent colored man in my town; or, I fought at Mechanicsville; or, Do not these Southern outrages make your blood boil? At these I smile, or am interested, or reduce the boiling to a simmer, as the occasion may require. To the real question, How does it feel to be a problem? I answer seldom a word.
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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.