A test

Hello,

How to explain why the underlined possibilies are wrong?

It was ___ so we didn't get it.
expensive enough
too expensive correct
enough expensive

It's ___ to read; I don't understand it at all.
enough difficult
too difficult correct
difficult enough

It's not ____ to sort things out.
enough late
late enough
too late correct

It's ____ to pass.
enough difficult
too difficult correct
difficult enough

It's ____ to walk- I'll take the bus.
enough far
far enough
too far correct
too much far

Are 'much enough' ever used together? For example,

- He ate ____ and felt ill.

enough much
much enough
too much


Thanks