28. I don’t think you’ve quite___the seriousness of the situation. You seem to know nothing about it.

A．recognized

B．mastered

C．grasped

D．Seized

易出现手、四肢大片脱皮并不留下色素沉着的疾病是（）。

A.风疹

B.麻疹

C.猩红热

D.幼儿急疹

E.水痘