【单选题】_______by the rising price of gas, many car owners use their cars less frequently. [ ]
【单选题】对一项社会调查研究的选题加以评判的主要标准,包括如下方面( )。
【单选题】Which group does NOT use posters frequently?
【单选题】The highest rate of skin cancers is found in teenagers who use sun lamps frequently.
【单选题】All of us thought _________ no use talking about some unpractical matters frequently.