Complex sentence: Orville wrote to decline the opportunity on June 30, as the Wrights were busy completing their deal with the United States Government the message was received by July 1, and Curtiss took to the air as requested on July 4, Independence Day.
Split into simpler sentences: Orville wrote to decline the opportunity on June 30, as the Wrights were busy completing their deal with the United States Government. The message was received by July 1, and Curtiss took to the air as requested on July 4, Independence Day.