硫酸铜溶液中加入过量铁粉，充分反应后过滤，留在滤纸上的物质是（）
A：铁粉和铜粉的混合物
B：铜粉
C：铁粉
D：硫酸亚铁和硫酸铜的混合物
Martin looks so well. We've never seen him ______ so well before.
当你想说鹿很矮，应说：（ ）
Today, WeChat（微信）becomes very popular, and more and more people like to use it to each other.
