No, "middle class" is a two-word phrase. It refers to a socioeconomic group that falls between the lower and upper classes, typically characterized by an average or comfortable income level, education, and lifestyle.
Yes it should be hyphenated.
Yes, it should be hyphenated.
Yes it should be hyphenated.
yes check-up should be hyphenated
It should be hyphenated.
"Field" is not hyphenated.
Yes, "low-to-intermediate" should be hyphenated when used as a compound modifier before a noun.
Yes it should be hyphenated.
No it shouldn't be hyphenated.
Yes it should be hyphenated.
Yes it should be hyphenated.