胎儿与胎膜都是由受精卵发育而来。
参考答案：对
An ecosystem consists of the living and nonliving things in an area ________ interact with one another.
A．that
B．where
C．who
D．what
京城内最负盛名的涮肉馆是( )。P96
A．东来顺
B．南来顺
C．西来顺
D．北来顺
