点拨：这是英语行文的一种方式，在句子开头用 To do……短语，并用逗号将其与句子的主体部分隔开，相当于汉语"若要做……的话"。例如：

若要收听国际新闻，请键入 "1"。{#blank#}1{#/blank#}

要想把它做对的话，你必须认真思考。{#blank#}2{#/blank#}

{#blank#}1{#/blank#}

—I eat eggs and hamburgers.

One day, a doctor {#blank#}1{#/blank#}  {#blank#}2{#/blank#} {#blank#}3{#/blank#}  {#blank#}4{#/blank#}  {#blank#}5{#/blank#}the king.

White lines {#blank#}1{#/blank#} the playing area {#blank#}2{#/blank#}several sections.

I took two apples. {#blank#}1{#/blank#} {#blank#}2{#/blank#} were yours.