lifestyle可不可数?如果可数的话那Chinese people’s lifestyle为什么没加s

lifestyle可不可数?如果可数的话那Chinese people’s lifestyle为什么没加s lifestyle和style是可数名词?如果前面加个different后面都要加s了? lifestyle是否可数 What kinds of changes has Chinese people’s lifestyle undergo diet和lifestyle是否可数? diet,lifestyle何时+s friendship可数为什么不在后面加s? 为什么可数名词后面要加S? "thing"可不可数?后面加不加s? problem意为问题 如果是many problem（problem后要不要加S,也就是问题可不可数 A:I'm making asurvey about people's lifestyle.______________ people到底可不可数啊?