How to differentiate to similar english words - What to use when

Like	As
used to compare only nouns	used to compare clauses
one verb in a sentence	two verbs in a sentence
Mostly at the beginning of the sentence

Say	Tell
You say something	You tell someone something
uses the word “to” or “that” before the object	uses an object directly following
cannot be used with reported questions

Would Rather	Prefer
must always be followed by a verb	may or may not be followed by a verb
when two things are being compared, would rather is followed by than	when two things are being compared, prefer is followed by to.

Hope	Wish
Possibility	Definitely
Something possibly happened or will possibly happen.	something definitely did not happen or definitely will not happen
hope can be followed by any verb tense	wish must NEVER be followed by a present tense verb or auxiliary verb
	wish is very similar to a contrary to fact or unreal condition.
	The word that can be added or omitted with wish. The sentence is correct either way