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sundials

Go outside on a sunny day and look 1) at your shadow'! Early 2) in the morning and late in the afternoon, it is long. At lunchtime, it 3) is very short. This is because the Earth moves around the sun and the sun is in a different place 4) in the sky at different times of the day. Sundials use shadows to tell the time. They 5) are the oldest way to tell the time!

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