- Do you know what Jack does all day? -- He spends at least as much time watching TV as he ________. A. studies B. does studying C. is studying D. does study 答案:B 本题考查句式spend some time in doing sth. 意为“花费时间干某事”,其中in可省略。does为代动词,代替前面的spends。句意为“你知道Jack整天干什么吗?”“他看电视的时间至少和学习的时间一样多”。 点P(a﹣1,a2﹣9)在x轴负半轴上,则P点坐标是________.
(﹣4,0)
【解析】【解析】
由题意得:a2-9=0且a-1<0,解得:a=-3.故答案为:(-4,0).