Johann David Wyss · 1743
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 285 of them.
Advanced — read it with glosses. 126,252 words in total; at 150 words a minute for a non-native reader, about 14 h 2 min to finish. Average sentence length 23.5 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 21,250 word families.
The opening of Swiss Family Robinson, 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.
For many days we had been tempest-tossed. Six times had the darkness closed over a wild and terrific scene, and returning light as often brought but renewed distress, for the raging storm increased in fury until on the seventh day all hope was lost.
We were driven completely out of our course; no conjecture could be formed as to our whereabouts. The crew had lost heart, and were utterly exhausted by incessant labour. The riven masts had gone by the board, leaks had been sprung in every direction, and the water, which rushed in, gained upon us rapidly.
Instead of reckless oaths, the seamen now uttered frantic cries to God for mercy, mingled with strange and often ludicrous vows, to be performed should deliverance be granted. Every man on board alternately commended his soul to his Creator, and strove to bethink himself of some means of saving his life.
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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.