An average of just 18.75cm of rain fell last year, making ______ the driest year since California became a state in 1850.
| A．each | B．it | C．this | D．one |
Do you consider it any good _____ psychology?
| A．to learn | B．to have learned |
| C．learning | D．having learned |
Lack of money led the company to a situation _____ they had to decide whether they should keep on with their production.
| A．when | B．where | C．that | D．which |
_____ by the advances in technology, many farmers have set up wind farms on their land.
| A．Being encouraged | B．Encouraging |
| C．Encouraged | D．Having encouraged |
_____ the police thought he was the most likely one, they could not arrest him since they had no exact proof about it.
| A．Although | B．As long as | C．If only | D．As soon as |
The wild flowers looked like a soft orange blanket _____ the desert.
| A．to cover | B．covered | C．cover | D．covering |