Standard 3

  Ch 11 Air, Water and Weather A. New Words 1) essential 2) pollution 3) colour 4) taste 5) scarcity 6) harvesting 7) evaporation 8) condensation 9) precipitation 10) water cycle 11) water vapour 12) weather 13) atmosphere 14) breeze 15) surroundings             B. Word Galaxy:   C. Explain the following terms. a. Season Ans - A season is a period of the year marked by changes in weather. Summer, winter, monsoon, autumn and spring are the five main seasons in India.   b. Weather Ans - The atmospheric conditions of a particular place at a particular time is called weather.   c. Wind Ans - Moving air is called wind.     D. Answer the following questions in 3 to 5 sentences. a. What is air pollution? Ans - When dust particles, smoke and other harmful substances mix with air, the air gets polluted. Polluted air is harmful for humans, animals and plants. When we inhale polluted air, it causes many health

 

  Ch:20 Modes of Communication   New words   1 digital communication 2 postal services 3 telephones 4 television 5 internet 6 communication 7 sign language 8 messengers 9 pigeon 10 newspaper 11 speed post 12 stamp 13 letter 14 radio 15 mudras Word Galaxy Answer the following questions a. What is an email? Ans. It is an electronic mail where we can send and receive  letters without using paper to write them on.   b. What do you understand by the term 'communication'? Ans. The exchange of information between people, through  speaking, writing or use of signs and symbols is known as  communication.   c. How does sign language help people who cannot hear? Ans. Sign language helps them to convey their feelings and  understand what others are saying.   d. What are the different uses of the internet? Ans. 1) The Internet gives a lot of information about political news  and sports.           2) The Internet has made our l