All of us are aware of the cause of this failure, so do not make the same mistake again.
A. well
B. very
C. rather
D. never.
网友回答
(答案→)A. well
B. very
C. rather
D. never.
解析：副词用法。Be well aware of 对…相当清楚；well修饰aware;句意：我们所有人对于这次失败的原因非常清楚，所以我们不会再犯同样的错误了。