If you have purchased the "formal-attire" suit, then I know that you are using a mobile device/ tablet, because the desktop version does not offer that option.
I'm sorry, but I do not know how to get rid of that feature. (I'm not even sure why they thought it was a good idea to offer it!)
As for bonus skills, it is a fairly common question.
Around about November/ December, they have been offering up "Christmas" as the third bonus skill.
I was in the initial beta group (3 years ago, now?) and it was actually the first bonus skill offered to us after they introduced lingots.
So I've always had it, and it doesn't go away once you do buy it. But it seems that it disappears and comes back based on the calendar date, not dependent on anything that you have done previously (you can be at a very "low" level of experience and still buy bonus skills.)
I wouldn't worry much about missing out, though, as it is fairly repetitive and largely idiomatic. And not useful, except at Christmas.
How can one spend lingots? If I knew, I'd tell you. I currently have 3,010 of them.
Back when the system used "hearts" to track your progress during a lesson (if you lost three hearts then you had to start the lesson over again), there was an option to buy a bonus "heart" for a small amount of lingots (was it 5? It's been so long now).
You can give them away; to people you like, or for comments that you like, but otherwise they are pretty useless.
I don't think that Duo knows what to do with them, now, but there would surely be a rebellion if they tried to take them away from some people.
I think it's a way of collecting "prestige" for some-- I have 2,000 lingots, and you only have 60!
Lui si trova in prigione ==> He finds himself in prison
what is the action/verb?
trova = (he/she/it) finds, verb
who does the action?
Lui = he, subject
what/who does the subject action (what does he find) ?
si = himself, reflexive pronoun
in prigione = in prison, propositional phrase
He himself finds in prison ==> He finds himself in prison
No, the best translation is "He is in prison". "Lui è in prigione" and "lui si trova in prigione" have the same meaning. "He can be found in prison", is probably the best literal translation. This translation captures the "nuances" of the sentence. "Lui si trova in prigione" is the same thing of "lui è in prigione", but using the verb "trovare" the sentence could say something like "if you have to meet him, you can find him in prison". But the gist of this sentence is "he is in prison". If you translate this sentence into "He can be found in prison", you catch "the nuances", but not the gist. The small differences between "Lui è in prigione" and "Lui si trova in prigione" make sense only in Italian. In English is "He is in prison".
My native language is Swedish, we have also a special verb for 'trovarsi' that in English is best translated with just 'be in'. Or like 'nicolads89' says, the nuance 'knowing where to find the person' (in prison). It has nothing to do with unexpected, or looking for oneself', it just means "being" in a place. In this case literal translation in English just makes it too complicated.