aware

Aware means you know that something is there or is happening. Aware of a smell of burning, aware that someone is standing behind you, aware of how late it has got.

It takes OF before a noun and THAT before a clause: aware of the risk, aware that the risk exists. Unlike most adjectives it lives after the verb, as in she is aware, I became aware, and it sounds wrong in front of a noun except in built-up compounds such as self-aware, safety-aware and environmentally aware. The noun is awareness, which turns up in raise awareness and awareness campaign, and the opposite is unaware, meaning the news never reached you. In a formal email or a complaint, please be aware that is a polite warning shot. There is a second, warmer sense too: an aware, informed public is one that understands a problem rather than merely noticing it.