Answer:
(i) The old man is very rich; he is not proud of his wealth.
(ii) The thief escaped; it was dark.
(iii) I saw the boy; he had won the medal.
(iv) Raj is very silly; she will believe anything.
Step-by-step explanation:
Semicolons can be used to combine two closely related independent clauses: parts of a sentence that can stand alone to make simple sentences.