Mr. Black his mother every Sunday.
A:visits
B:hurts
C:has
t℃时,两个装有100克水的烧杯中,分别加入不带结晶水的甲、乙物质各80克,充分搅拌。根据如图溶解度曲线判断,此时 ____ 溶液是饱和溶液,甲溶液的溶质质量分数是____ 。
我国的珍稀植物有____、____等。
Parents find it difficult _______ with their teenage children.