喷油器应经常保养校验，否则影响柴油机，致使工作不正常。
参考答案：对
从如图中选择相关的适合仪器，将其编号写在相应的空格处．
①写出仪器f名称：f：______．
②用上述仪器的序号填写：量取15.0ml的H2O用到______．
---Where did you save the drowning girl, ________ parents were both professors?
---It was from the lake ______ she often went fishing.
A．who; that
B．whose; that
C．whom; where
D．whose; where
