At that time, the general public was/ were not aware of the health risks.
那时，公众对各种危及健康的因素尚不了解。
She was aware that she was losing all sense of perspective.
她意识到自己正在失掉一切正确判断的能力。
I'm aware of Mark's reputation for being late.
我知道马克迟到是出了名的。
Were you at any time aware of a quarrel between the two of them?
你什么时候注意到他俩拌过嘴吗？
She slipped away without him being aware of it.
她悄悄离开，没有让他发觉。