We _____ into five groups to go to the old people's homes. We did many things to cheer them up. [     ]

A. divided

B. are divided

C. were divided

关于缺水的叙述下列哪项是错误的()

A．高渗性缺水细胞内缺水<细胞外缺水

B．低渗性缺水细胞外缺水>细胞内缺水

C．等渗性缺水时水和钠成比例急剧丧失

D．高渗性缺水缺水>缺钠

E．低渗性缺水又称慢性缺水或继发性缺水