Complex sentence: Under the rules it took nine years apprenticeship for a poet to become fully qualified, and they also set out the payment poets could expect--these payments varied according to the period of training the poet and the time of the year.
Split into simpler sentences: Under the rules it took nine years apprenticeship for a poet to become fully qualified. They also set out the payment poets could expect--these payments varied according to the period of training the poet and the time of the year.