How do you spell first?
Adverbs that are derived from ordinal numbers with the prefix in- (in-) are written with a hyphen. It turns out: firstly; Secondly; thirdly and so on Based on this rule, you can answer the question of how to spell first. Remember: write correctly “first”.
We also draw your attention to the typical mistake of using such adverbs. If you use “firstly” in the text, then at least “secondly” must appear. When a person uses the expression "first" in speech, he thereby indicates that there is something else that he is ready to express on the subject. Using only “first” in speech creates the effect of incompleteness, dangling. Nevertheless, such an error is quite common, so remember: where there is a “first” one, there must necessarily be at least a “second” one.