"In advance" how to spell?
Russian language can confuse anyone. What is it worth writing adverbs with prefixes. Now they are written together, then separately. So, let's understand: the word "in advance" how to spell?
There is a rule: an adverb formed by connecting a prefix with another adverb is always written together. Thus, the word “in advance” was formed by joining the adverb “earlier” with the prefix “for”: “Thank you in advance for your help.” The adverb answers the question here: "How do I thank?" - "Thank you in advance".
But be sure to pay attention to the context. From the meaning of the sentence, the meaning, and hence the spelling of words, changes drastically. In the sentence: “I thank you for the work done earlier” “for” - a pretext that refers to the noun “work”: I thank (for what?) For the work. That is, we get the adverb "earlier" with a preposition. You can test yourself by changing the sentence: “Thank you for the work done earlier.” Now it is clear that this is a case of separate writing.
Therefore, in order not to worry about the question: “in advance,” how do you spell it? Always pay attention to the context and meaning of the expression.