"우리는 무거운 책을 읽고 있어요."
Translation:We are reading a heavy book.
Exactly. The -ing form if you want :)
In English, progressive and continuous tenses seem to be the same. I didn't know about this distinction in other languages...
i was wondering the same thing and looked it up. naver says 무겁다 can also mean "serious", "grave" and "important", those meanings were not the first to come up, so i assume there are better ways to express them, but they are there. so there's that...
i also stumbled over the idiom 입이 무겁다 (heavy mouth) which means one can hold secrets well, so there's also this fun fact