Пре­об­ра­зуй­те, если это не­об­хо­ди­мо, слово REAL так, чтобы оно грам­ма­ти­че­ски и лек­си­че­ски со­от­вет­ство­ва­ло со­дер­жа­нию тек­ста.

In 1785, Jean Pierre Blanchard used a dog to test his parachute design. The dog was fine, and so was Blanchard when he used the parachute in 1793 to escape a balloon accident. These early parachutes didn't catch on because there weren't any flying machines around to make them ___________ useful.