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Self-Correct as You Read is a free printable Grade 4 English worksheet on going back over an information text to fix understanding, aligned to Common Core standard RF.4.4. It prints 2 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two pupils in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.

Set 17 of 25 · the same problems every time you open this link.

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Set 1 has all 25 in a single PDF. All 25 sets ask different questions.

Self-Correct as You Read

RF.4.4

NameDate

Read the text, then answer the questions.

1.Read the text, then answer the questions.

How Penicillin Was Found

In 1928 Alexander Fleming went on holiday and left a stack of dishes on a bench. Each held a colony of bacteria. When he came back, one dish had a spot of mould on it. Around the mould was a clear ring where the bacteria had died. Fleming realised the mould was producing something that killed bacteria. He named it penicillin and published a paper. Almost nobody noticed. Ten years later, Howard Florey and Ernst Chain read that paper and tried to make penicillin in quantity. That turned out to be the hard part: it took two thousand litres of mould fluid to treat one patient. By 1944 the problem had been solved and penicillin was reaching soldiers in the field.

  1. 1. What did he see around the mould?
  2. 2. What does "in quantity" mean here?
  3. 3. What is a "colony" of bacteria?
  4. 4. In what year did Fleming notice the mould?
2.Read the text, then answer the questions.

Lichen

A lichen is not one organism. It is a fungus and an alga living as one body. The fungus provides the structure and holds water. The alga photosynthesises and makes sugar. Separated, the fungus starves and the alga dries out. Because it needs no soil, a lichen can grow on bare rock, on gravestones and on the roofs of cars that have not moved for a decade. Lichens grow extremely slowly — some crustose species less than a millimetre a year. Scientists use that rate to date rock surfaces, a method called lichenometry. Lichens also absorb whatever is in the air. Where the air is dirty, they disappear, which makes them a living measure of pollution.

  1. 1. What two organisms make up a lichen?
  2. 2. How slowly can a crustose lichen grow?
  3. 3. What is lichenometry?
  4. 4. What does "absorb" mean here?

LessonPrint · RF.4.4 · Set 17 · free to copy for classroom use

Answer key — Self-Correct as You Read

Set 17. Prints on its own sheet.

  1. 1.1. A clear ring where the bacteria had died. 2. In quantity means in large enough amounts to treat patients — two thousand litres of mould fluid for one. 3. A group of bacteria growing together in one place. 4. 1928.
  2. 2.1. A fungus and an alga. 2. Less than a millimetre a year. 3. Using lichen growth rates to date rock surfaces. 4. Take in from the air around it.

Last reviewed 2026-09-05. Aligned to RF.4.4 of the Common Core State Standards for English language arts.