Writing as it is spoken, without paying attention to the rules of spelling and grammar, generates doubts and confusion. There are letters that sound practically the same, so one can stop writing to ruminate if a word is written with ll or y (balleta or bayeta?), with b or with v (pivón or pibón?). Other frequent errors for those who do not master the rules is not making a correct use of accents (exam or exam?; faith or faith?) or the letter hache (hermitage or hermitage?). The list of horrors can be extended even further if we add the failures that occur with many expressions. For example, this button: of course or of course, how is it written?

The truth is that it is enough to look a little at the structure to clear up any hint of doubt. The case at hand is an adverbial locution that acts as a discourse marker, an expression of assent or confirmation, headed by the preposition by and followed by the supposed noun. In summary, this expression, which is equivalent to of course or certainly or without a doubt, is always written separately, in two words: of course. Of course we’re going to the party / Of course I’m not going to see you again.

On the contrary, the term “of course”, written in a single word, is not included in the dictionary of the RAE, so writing it like this is a major error.

Another different thing is “of course”, in three words, which is correct as a prepositional phrase: Elena fought for her job. Of course, this form is never accepted to replace of course.

Of course there should no longer be any doubt. This case is much simpler than that of other locutions that give rise to doubts, such as about or about, in the middle or in the middle or the group likewise, likewise and itself.

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