【单选题】______ everything into consideration, and you will find that you’d better get well prepared ahead of time for the busy days _______.
【单选题】下列有关生态系统功能的叙述中,正确的是:() ①能量只能由较低营养级流向较高营养级 ②能量流动和物质循环都是可逆的 ③食物链中的营养级可以是无限的 ④生态系统中的能量最终以热能形式散失到环境中
【单选题】You ___________ your tooth pulled out before it rots completely. A. had better got B. had to get better C. had better to get D. had better get
【单选题】I think you’d better your bad habits before you marry.
【单选题】It's believed that________you work, ________result you'll get. [ ]
A.
the harder; the better
B.
the more harder; the better
C.
more hard; more better
D.
the more hard; the better
【单选题】You’d better _______ up late.
【简答题】请回答下列有关生态系统的问题。 (1)生态系统是由_____________两种成分组成。 (2)下表列出三种生态系统在地球上所占面积比、生产者的净生产量、现存量以及被食量。 ①热带雨林的生产者主要是____________,海洋生态系统的生产者主要是___________。 ②影响热带雨林净生产量的主要无机环境因素是_________,而影响海洋生态系统的则是____________。 ③据表资...