I like the book “20,000 leagues under the Sea” by Jules Verne since one of my sisters studied oceanography and another sister of mine lives in France. The vocabulary after each paragraph of the book certainly helps a lot. For words not in the vocabulary, I can use an app called “wiki СЛОВО”, which quickly gives an English word for a given Russian word (like ЛЬЕ) plus all those possible declensions. At the end of each chapter, there are questions with possible answers that a reader needs to choose.
