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Little Duck is {#blank#}1{#/blank#}（watch）the sun going down. It is {#blank#}2{#/blank#}（get）lower and lower, but his shadow is getting {#blank#}3{#/blank#}（long）and {#blank#}4{#/blank#}（long）.
“Why is that?” Little Duck asks his friend Old Tree, “You are {#blank#}5{#/blank#}（old）and {#blank#}6{#/blank#}（small）than me. Tell {#blank#}7{#/blank#}（I） why is my shadow longer when the sun gets lower?”
