【简答题】In my memory, my parents never me when I did something wrong.
【单选题】My parents never let me ______ alone.
【简答题】My parents never __ (上大学)in a university.
【判断题】They never set foot in a university. My parents never received a college education.
【单选题】下面不是数据库系统必须提供的数据控制功能的是
【判断题】动态环境的特点是缺乏新的行业进入者。( )
【单选题】相同功率下,卤钨灯的寿命为白炽灯的( )倍。