Level: E DRA: 8 Science Strategy: Visualize Word Count: 180 1.5.22 Build Vocabulary by Kendrick West HOUGHTON MIFFLIN Online Leveled Books 1431840 H O UG H T O N M IF F L IN by Kendrick West PHOTOGRAPHY CREDITS: Cover © SBP/Alamy; 1 © ARCO/D. Usher/age Fotostock; 2 © Blickwinkel/Alamy; 3 © Martin Fowler/Alamy; 4 © Mark Duffy/Alamy; 5 © Wiz Data, Inc./Alamy; 6 © Konrad Wothe/Minden Pictures; 7 © ARCO/D. Usher/age Fotostock; 8 © SBP/Alamy; 9 © Blickwinkel/Alamy; 10 © Wim Weenink/Foto Natural/ Minden Picture Copyright © by Houghton Mifflin Harcourt Publishing Company All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying or recording, or by any information storage and retrieval system, without the prior written permission of the copyright owner unless such copying is expressly permitted by federal copyright law. Requests for permission to make copies of any part of the work should be addressed to Houghton Mifflin Harcourt School Publishers, Attn: Permissions, 6277 Sea Harbor Drive, Orlando, Florida 32887-6777. Printed in China ISBN-13: 978-0-547-42734-8 ISBN-10: 0-547-42734-4 1 2 3 4 5 6 7 8 0940 18 17 16 15 14 13 12 11 If you have received these materials as examination copies free of charge, Houghton Mifflin Harcourt School Publishers retains title to the materials and they may not be resold. Resale of examination copies is strictly prohibited. Possession of this publication in print format does not entitle users to convert this publication, or any portion of it, into electronic format. Look at the birds. They will have baby birds soon. They will build a nest to keep the babies safe. 2 Look at the nest. The birds use mud to build their nest. They may come back to the nest for many years. 3 Look at the mother bird. She lays eggs. The mother and father keep the eggs warm until the babies hatch. 4 Look at the eggs. An egg begins to move. A baby bird is inside. Th