How do we make bridges? Do animals have bridges? Find out more about the science of building bridges, big and small. Do You Know? is a series of levelled non-fiction books featuring video content, project work and critical-thinking activities to motivate and engage young learners. Covering a range of STEM topics, Do You Know? takes an enquiry-based approach, developing children's language, communication and investigation 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. Big Bridges, a Level 1 Reader, is Pre-A1 in the CEFR framework and supports YLE Starters exams. Short sentences contain a maximum of two clauses, using the present tense and some simple adjectives.