【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
【多选题】读写器对接受到的信号进行()传给后台计算机控制器。
【单选题】下列有关生态系统中食物链与能量流动的叙述,不正确的是( )
A.
能量经食物链流动时只能从较低的营养级流向较高的营养级
C.
初级消费者含有的能量越多,次级消费者获得的能量越少
D.
生态系统中的能量最终以热能的形式散失到环境中
【单选题】下列生态系统的功能叙述中不正确的是
B.
人们可通过增加食物链营养级提高对能量的利用率
C.
能量流动和物质循环可以较长时间地保持动态平衡
【单选题】If you want to be thinner and healthier, you'd better eat _____food and take _____exercise. [ ]
【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
【判断题】Before you register a business name and get your license, you'd better check with the local Administration of Industry and Commerce to make sure the name you chose is not already taken.()
【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...