第25题: [单项选择]A new water boiler was installed in our building last week, which could provide hot water to the students. A. inspected carefully B. placed in service C. undertaken with care D. undone casually 参考答案:B 答案解析:inspect carefully仔细调查;be placed in service安装投入使用;undertake with care谨慎行事;undo casually随意地解开。因为instal