The word is spelled as you have done in the question.
The correct spelling is "solemn" (serious, formal).
Answervotre, vos (formal) Answerton, tes (informal)
Most people use "incl." However, for formal writing, you should just spell it out. This is true of most abbreviations in formal language.
There are no distinct spellings other than the formal English, "suggestion".
The most likely word is "introduction", a prelude, or making a formal meeting between strangers.
아니(informal) or 아니요(formal)
Δημήτρης Δημήτριος (formal)
To receive a formal request to attend a function is to be invited.
The correct spelling is "solemn" (serious, formal).
The correct spelling is tuxedo (formal wear, abbreviated tux)
e tu (informal) e lei (formal)
Was machst du? --informal Was machen Sie? --formal
The word referring to a formal event is spelt ceremony.
Did you spell it correctly? Betrothal is a formal state of engagement to be married. Historically betrothal was a formal contract, blessed or officiated by a religious authority
Frequently invitations will use the British spelling, "honoured."
bajo tu/su encanto (informal/formal)
"Thru" is the informal spelling. The correct formal spelling of the word is "through".