天空有两群鸟,一群鸟有12只鸟,加法算式为____,乘法算式为____。
选出恰当的应答语。
A.There was no computer room.
B.I looked it up on the Internet.
C.I went to Mountain Tai.
D.He tripped and fell in the race.
E.I went there by plane.
( 1 )____( 2 )____( 3 )____
( 4 )____( 5 )____
下列关于美国生理学家坎农对内环境稳态维持机制的解释,以下哪一项是正确的()