Issue with newly created action

Here is the code I am having trouble with:

[code]Understand “use [carried thing] on [something]” as using.
Using is an action applying to one carried thing and one visible thing.

Carry out using:
now aufmerksam of something is true;
say “Der Kontaminierte ist jetzt auf dich aufmerksam, du solltest sofort den Raum verlassen, er wird dir aber auch sofort folgen.”.[/code]
Don’t be confused by the German text. When I tried writing Kontaminierter(just a kind of person created by me) instead of something it didn’t work out either. The compiler spits out the following piece of text:

Problem. In the sentence 'now aufmerksam of something is true', it looks as if you intend 'aufmerksam of something' to be a property, but 'a thing' is not specific enough about who or what the owner is. How can I access this boolean value and change it? I also wrote a check-statement which checks if something is a Kontaminierter, so logically if the action was to be carried out it would have to be a “Kontaminierter” and therefore it would in any case have this truth state. Please help me :/.

As the error says, “something” is too vague. If you want to refer to the thing you’ve called [something] in the grammar line it’s “the second noun”, so “now aufmerksam of the second noun is true”.

Tangentially related notes: it’s very uncommon to make object properties that are explicitly boolean values because “normal” properties are boolean by nature, so you’d typically have “a person can be aufmerksam” and here you’d set it with “now the second noun is aufmerksam”. It might also be more convenient to call the action “using it on” so you can then more easily write rules that are something like “check using the mind reader on the guard” instead of having to separately check the noun and the second noun.

Thanks for your quick reply. I wrote “now aufmerksam of the second noun is true;” in the future I try to remember that you don’t have to explicitely state for a variable to be a truth state. I changed the action to “using it on”, but I didn’t have any issues with these check-statements in the first place.