- 试题详情及答案解析
- Every possible means ______, but none proves successful.
| A．has tried | B．have been tried |
| C．is being tried | D．has been tried |
- 答案：D
- 试题分析：考查动词的时态和语态。句意：每种方法都已经尝试过了，但没有一个是成功的。根据but none proves successful可知已经尝试过了，try与means之间是动宾关系，故选D项。
考点 : 考查动词的时态和语态