与听课时间
之间的关系满足如图所示的曲线。当
时，曲线是二次函数图象的一部分，其中对称轴为
；当
时，曲线是函数
图象的一部分。根据专家研究，当注意力指数
的函数关系式；
在一个草原生态系统中，生产者是（ ）
| A．鼠 | B．草 | C．兔 | D．鹰 |
在一个草原生态系统中，生产者是（ ）
| A．鼠 | B．草 | C．兔 | D．鹰 |
在光合作用实验里，如果所用的水中有0．44%的水分子含18О，二氧化碳中有0．68%的二氧化碳分子含18О。那么，植物进行光合作用释放的氧气中，含18О的比例为-----（ ）
| A．0．20% | B．0．44% | C．0．68% | D．0．88% |
---Is Jack good at basketball?
----Yes._____basketball he is also good at table tennis.
----Yes._____basketball he is also good at table tennis.
| A．Except | B．Besides | C．But | D．Beside |
---Is Jack good at basketball?
----Yes._____basketball he is also good at table tennis.
----Yes._____basketball he is also good at table tennis.
| A．Except | B．Besides | C．But | D．Beside |
----Could you get home at five o’clock?
---- ________I’ll have a meeting at that time .
---- ________I’ll have a meeting at that time .
| A．I hope so. | B．Yes,I think so. | C．I’m afraid not | D．I’m afraid so. |
I feel my stomach terrible.I think I ate _____at lunch time .
| A．something bad . | B．something good | C．bad something | D．good something |
There ____more cars now in our country.
| A．have | B．are | C．is | D．has |
What_____you do if you had a million dollars ?
0 22499 22507 22513 22517 22523 22525 22529 22535 22537 22543 22549 22553 22555 22559 22565 22567 22573 22577 22579 22583 22585 22589 22591 22593 22594 22595 22597 22598 22599 22601 22603 22607 22609 22613 22615 22619 22625 22627 22633 22637 22639 22643 22649 22655 22657 22663 22667 22669 22675 22679 22685 22693 159627
| A．would | B．will | C．did | D．do |