Mrs Marks bought a printer(打印机)yesterday．She was h{#blank#}1{#/blank#}because she could print anything she wanted at any time．H{#blank#}2{#/blank#}，after about an hour,she was angry because she couldn't print the colour blue．All the other c{#blank#}3{#/blank#}printed fine，except blue，which was very unusual．

    She d{#blank#}4{#/blank#}to call the after-sales service department(售后服务部)to help her solve the problem．David answered the phone．He t{#blank#}5{#/blank#}everything he could think of to help Mrs Marks．He asked her to reinstall(重新安装)the programme，to reboot(重新启动)the computer and to turn the printer on and off. N{#blank#}6{#/blank#}of these things helped．

    After hours of trying the problem s{#blank#}7{#/blank#}wasn't solved．Finally,David asked Mrs Marks if he could go to her h{#blank#}8{#/blank#}and try to solve the problem in person．Mrs Marks agreed，and t{#blank#}9{#/blank#}him her address(地址)．When he arrived at her house,she showed him her computer and the printer．David u{#blank#}10{#/blank#}what the problem was right away.He told her，"From now on，print on white paper instead of blue!"