Someone is one word when you are referring to a person.
BOTH!
Everyday is an adjective.
Every day is used like every month or every year.
I brush my teeth every day, it is one of my everyday activities.
two words, it will become : day long
"One day" is two words.
Its not one word, its actually two words: Pax Romana.Its not one word, its actually two words: Pax Romana.Its not one word, its actually two words: Pax Romana.Its not one word, its actually two words: Pax Romana.Its not one word, its actually two words: Pax Romana.Its not one word, its actually two words: Pax Romana.Its not one word, its actually two words: Pax Romana.Its not one word, its actually two words: Pax Romana.Its not one word, its actually two words: Pax Romana.
Yes, unless you are talking about someone's birthday and it is one word.
it is two words
Cookbook is one word - If it were 2 words, you'd be suggesting to someone to cook a book for your consumption. That makes no sense. That suggests that Ice Cream should be 1 word.
No, the word "downstairs" is a single word, not two words.
It's one word.One word as an adjective; two words as a noun
The possessive form someone's is one word. The plural would rarely be used (e.g. the someones in the various crimes proved to be a single individual).
in-house - two words, hyphenated.
Car sick is two words.
It is one word
The word "in between" implies that there are two words on either side of it.
Two words - "one day".