Can you explain this rule to me in simpler words? Correct. However, some people would say "in more simple words", and it wouldn't sound bad. He dreamt of buying a house beside the sea. Correct. However, some people would say "dreamed", which is an acceptable variant of the past tense. What do you dream of? Correct. With the verb "dream," you can also use the preposition "about". "To dream of" expresses a desire to obtain a goal. "I dream of buying a house beside the sea." That is, buying a house by the sea is my goal. "I dream about buying a house by the sea" describes an actual dream I have while I'm asleep.