选择合适的搭配。
明亮的____ 河水
干净的____ 教室
清清的____ 地面
洁白的____ 话语
亲切的____ 云朵
抛物线y=-x2+bx+c的部分图象如图所示,若y≥0,则x的取值范围是( )
抄写下列句子。
①Time for music class.
②It's 8 o'clock .It's time for English class.
③Hurry up .It's time to go to school.
④It's 9:00 .It's time to go to bed.