重症胎盘早剥临床表现错误的是()
A.恶心、呕吐、出冷汗
B.子宫呈板状硬、压痛
C.多量 * * 流血
D.突然发生的持续性腹疼
E.胎心、胎位不清
参考答案:C
While Mary ___ a letter, the children were playing outside.
A.wrote
B.writes
C.is writing
D.was writing
某元素原子的最外层电子数是次外层电子数的3倍,且最外层电子数与次外层电子数之和小于10.该元素为( )
A.锂
B.铍
C.氧
D.钙