text: const movie = {
      title: 'a',
      releaseYear: 2018,
      rating: 4.5,
      director: 'b'
  };
  
  showProperties(movie);
  
  function showProperties(obj) {
      for (let key in obj)
          if(typeof obj[key] === 'string')
              console.log(key, obj[key]);
  }