It depends on the meaning. Some examples:
'He became disillusioned of his belief that she loved him.' (Disabused.)
'I am disillusioned with this treatment; it doesn't seem to be working at all.' (Disappointed with something that has been going on for some time.)
'He was disillusioned at the reaction to his new play.' (Disappointed with something that happened.)
Those do not constitute an exhaustive answer.
The preposition that typically follows the word "disillusioned" is "with." For example, "She felt disillusioned with the company after learning about their unethical practices."
The preposition in the word "supply" is "up."
No, the word "when" is not a preposition. It is an adverb or a conjunction used to indicate time or a condition.
No, the word "I" is not a preposition. "I" is a pronoun, specifically a subject pronoun that is used to refer to oneself.
No, the word "early" is an adverb, not a preposition. It is used to describe the timing of an action or event.
No, the word "away" is not a preposition. It is typically an adverb that describes movement or distance.
The American people were disillusioned in the 1970s.
Disillusioned is used as an adjective. The more she experienced behind the scenes, the more disillusioned she grew with the entire political process.
The preposition in the word "supply" is "up."
No the word every is not a preposition.
No, the word "when" is not a preposition. It is an adverb or a conjunction used to indicate time or a condition.
No, it is not a preposition. The word explore is a verb.
No, it is not a preposition. The word thing is a noun.
Yes, the word among is a preposition.
No, the word "I" is not a preposition. "I" is a pronoun, specifically a subject pronoun that is used to refer to oneself.
No, the word "away" is not a preposition. It is typically an adverb that describes movement or distance.
No, the word "early" is an adverb, not a preposition. It is used to describe the timing of an action or event.
No, it is not a preposition. The word travelers is a plural noun.