读一读, 找出对应的选项。① He is talking in the library. {#blank#}1{#/blank#} A. Keep your desk clean.
② We are playing a game. {#blank#}2{#/blank#} B. Keep to the right.
③ She is colouring at her desk. {#blank#}3{#/blank#} C. Take turns.
④ They are walking on a bridge. {#blank#}4{#/blank#} D. Talk quietly.