______ on ten years of observation and study, the theory shows that every one dreams every night, whether they realized it or not.
| A．Basing | B．Based | C．Being based | D．Having based |
Without enough food, many birds didn’t ________ the winter.
| A．serve | B．surf | C．surprise | D．survive |
---Sorry, I’ve got an important appointment at 9 o’clock and I can’t _______ to miss it.
| A．manage | B．help | C．wait | D．afford |
Little Tom was so enthusiastic about learning Chinese and after six months, he could speak it ______ fluently.
| A．professionally | B．correctly | C．pretty | D．locally |
This is a complex operation. A team of nurses _____ the doctor in performing the operation.
| A．trained | B．assisted | C．interviewed | D．added |
The conflict between economic development and environmental protection, if not appropriately _________, can cause disastrous consequences in daily life settings.
| A．being managed | B．to manage |
| C．managed | D．managing |