Begun

verb

1. To start, to initiate or take the first step into something.

   "I began playing the piano at the age of five.   Now that everyone is here, we should begin the presentation."

2. To be in the first stage of some situation

   "The program begins at 9 o'clock on the dot.    I rushed to get to class on time, but the lesson had already begun."

3. To come into existence.