下列腺体中,除哪一个外,其余腺体的分泌物均直接进入血液中? ( )
A:肾上腺
B:垂体
C:胰岛
D:肠腺
My grandfather would be fine for a while, but would then fall suddenly ill and have to________the hospital.
下面四个几何体中,俯视图不是圆的几何体的个数是( )