Extensive reading means reading many easy books in English. You do not use a dictionary. If you do not understand a part, you skip it.

Does this help? Many studies say yes. It helps your reading, and it can improve reading speed. In Japan, students who read more became faster readers.

But new words are often forgotten if you meet them only a few times. So also study new words with cards.

In Japan, many students study English by translating short texts sentence by sentence. Extensive reading takes the opposite approach: learners read large amounts of easy books for pleasure, without a dictionary. Two meta-analyses published in 2015 and 2016 found that extensive reading has a small to moderate positive effect on reading ability. Reading speed is one area where gains have been shown.

In a one-year study of Japanese university students, those who read many easy books for pleasure became faster readers than those in intensive reading classes, and the more they read, the more their speed improved. However, extensive reading is not a magic way to learn new words. One study found that words met only a few times in a graded reader were largely forgotten three months later.

Japanese learners are familiar with intensive reading, the careful analysis and translation of short passages. Extensive reading inverts this approach: learners consume large quantities of easy material for enjoyment, skipping unknown words rather than consulting a dictionary. Two meta-analyses have assessed its effectiveness. A 2015 synthesis in TESOL Quarterly reported a moderate effect, with an effect size of around 0.5, and a 2016 analysis found small to moderate gains in reading proficiency that varied with learners' age and with whether English was a foreign or second language.

Reading rate is one area where gains have been shown. A year-long study of Japanese university students showed that those who read easy books for pleasure increased their speed more than those in intensive reading classes, and that greater reading volume produced greater gains. Extensive reading has limits, however.

When researchers measured how many new words learners picked up from a single graded reader, words encountered only a few times were largely forgotten after three months. Interpretation is further complicated because studies differ in how reading volume was recorded and in what comparison groups received. Extensive reading may work best for making familiar language automatic, while new words still need deliberate study.