某兴趣小组的同学做“探究草履虫对外界刺激做出反应”，假如你是其中一名成员，请完善下列内容．
—It's a long story, but you will find that there are few new words in it .—Good! it will be too hard for children.
A: Touch this bag. Is it____? B: No. It's hard.
如图是一种投入使用的新型安全校车，中考期间，某中学的学生乘坐这种新型安全校车到18km外的考点参加考试，校车行驶了30min后安全到达考点，
（激发态）
