A:雌:雄=1:1
B:雌:雄=1:2
C:雌:雄=3:1
D:雌:雄=4:1
有些幼儿常服钙片,仍因缺钙患佝偻病,原因可能是缺乏( )
I a camera two weeks ago but I haven't had a chance to use it.
按拼音写汉字
qīn nì____ zhuó mo____ jì xù____