Слово "useful". Англо-русский словарь Мюллера

The chief beauty of this book lies not so much in its literary style, or in the extent and usefulness of the information it conveys, as in its simple truthfulness.

And since it is beautiful, it is truly useful."

Berlioz's high tenor rang out in the deserted walk, and as Mikhail Alexandrovich went deeper into the maze, which only a highly educated man can go into without risking a broken neck, the poet learned more and more interesting and useful things about the Egyptian Osiris, [9] a benevolent god and the son of Heaven and Earth, and about the Phoenician god Tammoz, [10] and about Marduk, [11] and even about a lesser known, terrible god, Vitzliputzli,'[12] once greatly venerated by the Aztecs in Mexico.

Now, falsetto register may not be very useful most of the time,