A:ordered
B:was ordered
C:has been ordered
D:has ordered
今年世界环境日,某校组织的保护环境为主题的演讲比赛,参加决赛的6名选手成绩(单位:分)如下:8.5,8.8,9.4,9.0,8.8,9.5,这6名选手成绩的众数和中位数分别是( )
When you see an English film or talk with native speakers, observe their facial expressions and g____.