How Much Vocabulary One Reading Leaves

You’re reading a news story in English and meet a word. You look it up, nod, and read on. When you finish, you close the page. The next week you see the word somewhere else. It looks familiar, but the meaning won’t come.

Many people learn vocabulary from word lists. Asked another way: if you don’t study, and only meet words in context as you read, how many does one reading leave? The two sections below each cover one design and what three studies measured.

01Keep the word as you read it

In 2003, Waring and Takaki asked 15 Japanese female university students (aged 19–21) to read a graded reader of A Little Princess at the 400-word level, about 5,872 words long, which took them 56 minutes on average. Twenty-five words in the book had been replaced with spellings the students had never seen, standing for simple meanings such as house and yes. They were tested straight after reading, then again a week and three months later, and had to write each word’s meaning.⁠[1]

Straight after reading, they could write the meaning of 4.6 of the 25 words on average; a week later, 1.9; three months later, 0.9 (14 students took this test). Of the words that appeared fewer than 8 times in the book, none were left after three months. The authors concluded that reading one book leaves about one new word. They also noted that two of the words were especially easy to guess; without those two, the rate would drop by about half again.⁠[1]

Another study also counted how often each new word appeared. In 1998, Horst, Cobb and Meara had 34 lower-intermediate university students in Oman read a whole simplified novel, The Mayor of Casterbridge, 21,232 words long: the teacher read it aloud in class while they followed along, over about six one-hour lessons within ten days. Before and after reading, they took the same multiple-choice test on 45 target words.⁠[2]

Before reading, the students already knew about half of them. Afterwards, they knew 4.62 more on average, about 22% of the words they hadn’t yet learned: one new word in five. The book contains 222 words the students hadn’t studied in class, and two-thirds of them appear only once in the whole book. Even for words that appeared eight times or more, only about half of the students who hadn’t known them knew them after reading.⁠[2]

WordLinea’s approachWhen you meet a word you don’t know, select it on the page, and the word, its sentence and where you found it go into your library together. There’s no waiting for it to turn up in the next article.

02Kept words come back on their own

What happens with more encounters? In 2010, Pellicer-Sánchez and Schmitt asked 20 Spanish university graduates, advanced learners of English, to read the unsimplified novel Things Fall Apart, about 67,000 words, within a month. It contains 34 Igbo words, each appearing between 1 and 36 times. Two to five days after reading, the researchers interviewed each reader to see whether they could give the words’ meanings.⁠[3]

Of the words met 1 to 8 times, readers could give the meaning of 7%; of those met 10 times or more, 55%. The authors suggest that for these readers, learning starts to pick up somewhere around eight to ten encounters, though individuals varied widely.⁠[3]

The authors also record one case, which they mark as anecdotal: the top scorer guessed there would be a test, underlined the Igbo words while reading and went back over them afterwards. They recommend adding practice in active recall rather than waiting for words to appear this many times in a book.⁠[3]

WordLinea’s approachWords in your library come back when they are due, each with a question, with no waiting for them to turn up by chance in the next article. Why it is a question is explained in Memory Is Made in Recall.

03Two designs, one principle

These three studies measured reading itself: how many words remain once the reading is done. They found the same thing: one reading leaves very little. Saving a word as you read it is a design that starts from there.

A word you read doesn’t have to wait to be met again by chance: keep it when you meet it, and let it come back.