Instruction
1
In the case of the word "for" is necessary to determine what was going on. If the proposal refers to the flow of the river, in this case "during" is a preposition and a noun neuter, standing in the prepositional or the accusative case, answering the question "where?" or "where." Then you should write "for river" (to the question "where?") and "over the river" (to the question "where?"). If we are talking about time frames, then this phrase is an adverb and is always written " for": for one year, in the course of the day.
2
The same thing happens with the phrase "in conclusion", "in consequence of", "continuation".
Remember that between a preposition and a noun, it is always possible to insert some adjective, like "rapid river", whereas the adverb one, even if written separately. Compare:
In (this) the result of a lot of white spots.
Consequently, the case will not be closed.In conclusion, he said that he was glad to see.
In (prison) he had been in for two years.In continuation of the above, I note that this is not the limit.
In continuation to the book you will learn what the outcome of this story.
3
There are more phrases, the writing of which depends on the context. Compare:
That's not what I had in mind. In these circumstances we could not come to agreement.
I don't know anything about it. We put the money in (Bank) account.
We didn't want to go to (this) meeting. They walked towards each other.
4
Remember the words that are always written only and nothing else: "later", "like", "eve". Always written separately: "unlike", "in", "because", "as".