A:NaCl晶体 BaSO4
B:铜 二氧化硫
C:液态的醋酸 酒精
D:熔融的KNO3 硫酸溶液
一般情况下,下列细胞的分化程度由高到低的顺序依次是( )
①神经细胞 ②受精卵 ③胚胎干细胞 ④造血干细胞.
One of the most effective ways to reduce is to talk about feeling with someone you trust.
根据中文意思完成句子。(1)你为什么不查查字典呢?____ look up the words in your dictionary?(2) 他差不多和他父亲一样高了。He is almost____ his father.(3)你看起来不高兴,怎么啦?You look unhappy. ____ you?(4)养成良好的学习习惯是重要的。____ good learning habits.(5) 李刚帮妈妈做完家务才做作业。Li Gang____ the housework.