In Sydney, there’s only ________ average of 23 days a year when ________ sun doesn’t shine.
| A．the, the | B．an, / | C．an, the | D．the, / |
A ___________ identification card is required when you purchase foreign money from the Bank of China.
| A．valid | B．fruitful | C．beneficial | D．effective |
The observations which he reported __________ marketing bothered his boss a lot.
| A．being concerned | B．concerned | C．be concerned | D．concerning |
Remember when you learned to water ski, David? _________ you skied more, you got better and better. It’s the same with language study.
| A．although | B．while | C．as | D． unless |
________ over everything whenever we want to make a decision, many people believe, and we will have less chance of making mistakes.
| A．To think | B．Think | C．Thinking | D．Thought |
Of the equipment we have produced, this sells best, for it has the advantage over ________ of working efficiently.
| A．the others | B．the rest | C．others | D．another |