【简答题】As we all know, iron is the (useful) ______ metal in the world.
【单选题】皂苷类化合物一般不适宜制成注射剂,是因为具有
【单选题】As we all know, thick forests are the natural ______for birds, animals and insects, and we must forbid cutting trees without any limitation.
【简答题】The party cares for us y______, as we all know.
【单选题】皂苷类化合物一般不适宜制成注射剂,是因为
【单选题】皂苷类化合物一般不适宜制成注射剂,是因为()
【单选题】Diamond, _________, is the hardest of all materials.
【简答题】As we all know, fresh air is ______ to our health. (benefit)
【简答题】We all know that the plan is divided into three parts. (翻译)