Use this A2-B1 ESL science reading passage to learn how a clock works. It includes key vocabulary, reading comprehension questions, and answers for English learners.Reading LevelA2-B1Word Count235 wordsReading PassageA clock is a tool that shows time. It helps people know when to wake up, go to school, eat, work, or sleep.A clock must measure time in a regular way. Many clocks do this by countin..