Contracted words.
"After school" is typically written as two words.
Chess player is written as two words.
"Pogostick" is typically written as one word.
"all day" is typically written as two separate words.
Two words.. one hundred.
"Crash site" is typically written as two words.
"Fact sheet" is typically written as two words.
One and two hundredths.
It is not one nor two words. It is hyphenated, just as it is written in the question.
Businessmen is often written as one word. It can be two words or even hyphenated
"Sleep talking" is typically written as two words.
"Study hall" is typically written as two words.