All the athletes _______ the nice service during the London Olympics.
A:were pleased
B:were pleased with
C:were pleasure
D:were pleasure with
命题“∀x∈R,x3﹣x2+1≤0”的否定是( )
下列有关细胞的说法,正确的是( )
利用光导纤维传输信息时其实是光的一种____ (选填“反射”或“直线传播”)现象.少数青少年由于沉迷于网络而用眼过度导致近视,近视眼看远处物体时,物体的像落在视网膜的____ (选填“前方”或“后方”),需要配戴____ 透镜进行矫正.