判断下列说法中,p是q的充分条件的是_______.①p:“x=1”,q:“x2-2x+1=0”;②设a,b是实数,p:“a+b>0”,q:“ab>0”. 答案:【答案】①【解析】根据充分条件的定义,结合特殊值法进行判断即可.①:当x=1时,显然x2-2x+1=0,因此由p可以推出q,所以p是q的充分条件,故本说法符合题意;②:当时,显然符合a+b>0,但是ab>0不成立,因此由p推不出q,所以以p不是q的充分条件,故本说法不符合题意.故答案为:①With more forests being destroyed, huge quantities of good earth each year. A. is washing away B. are being washed away C. are washing away D. is being washed away