Yes. Do-over is a hyphenated word.
You do not need to hyphenate.
You do not hyphenate the number.
You hyphenate it only at the hyphen.
Don't hyphenate; ongoing is one word.
You don't hyphenate the words 'thank you'
I think it's more accepted to hyphenate it.
Can you, or should you? You can hyphenate it if you're moving between lines in a paragraph and need to break up the word. You shouldn't hyphenate it normally.
You can hyphenate the word improvement like this: im-prove-ment.
You mean at the end of a line? Well it depends on how much room you have hyphenate at a syllable is probably best. If you have little space before the end of the line don't hyphenate a word. You could hyphenate like this trans- portation.
No...
You can hyphenate 3 bedroom when it is used in a list. It is usually not hyphenated when it is used by itself.
Phrases used as adjectives or adverbs, such as "over-the-hill gang" or "run-of-the-mill answer", would be hyphenated.