function Book(title, author, pages, read) {
  this.title = title;
  this.author = author;
  this.pages = pages;
  this.read = read;
  this.info = function() {
    return `${title} by ${author}, ${pages} pages, ${(read) ? "read" : "not read yet"}`;
  };
}

const myBook1 = new Book("The Hobbit", "J.R.R. Tolkien", 295, false);
const myBook2 = new Book("Pan Tadeusz", "Adam Mickiewicz", 692, true);
const myBook3 = new Book("Quo Vadis", "Henryk Sienkiewicz", 563, false);

console.log(
  myBook1.info(),
  myBook2.info(),
  myBook3.info()
)