植入后的子宫内膜称()
A.基膜
B.蜕膜
C.基蜕膜
D.胎膜
E.黏膜
参考答案:B
解析:围生期Ⅱ:从妊娠满20周(即胎儿体重≥500g或身长25cm)至产后4周;
平面内有A、B、C、D四个点,可以画______条直线.
In a sport team each player has a clear role, and there are few occasions ______ members are confused or uncertain of their roles.
A.why
B.where
C.when
D.in which