【最新】四年级英语下册《Unit 15 communication》（Lesson 88） .ppt

Unit15 Communication Lesson88,人教新起点四年级英语下册,Do you know how people sent messages years ago,fire and smoke,pigeon,flag,letter and stamps,computer,telegram,telephone,Internet,send an e-mail,Read and write. 1.We can send messages by fire and_. 2.Other people can use _ to send and receive messages. 3.Sailors on a ship can use _ to signal other ships. 4.We can also use letters and _. 5.We can also use _, _ , a