How do animals move? Who flies fast? Who walks slowly? Find out about different animal speeds in this BBC Earth reader. The Ladybird Do You Know? graded readers series comprises a range of non-fiction STEM titles for young learners of English. Covering a variety of topics, Do You Know? adopts an enquiry-based approach, and includes motivating video content, project work and critical thinking activities to develop students' linguistic and twenty-first century skills. Recommended for children aged 7+, there are four levels progressing from CEFR level Pre-A1 to level A2. Each reader is accompanied by online video content, audio, video and comprehension activities, and suggestions for project work. Fast and Slow, a Level 4 Reader, is A2 in the CEFR framework and supports YLE Flyers exams. The longer text is made up of sentences with up to three clauses, more complex past and future tense structures, modal verbs and a wider variety of conjunctions.