Usar "precursory" en una oración

1. “So you’re saying, that, is the precursory to the game? But it’s never been published

2. The medic began a precursory check, while the pilot, at Tam’s request, circled the area twice, searching for Tam’s alleged boat

3. Such a thing is only a precursory attempt to instill within whoever wanders here a sense of hopelessness that there is nothing when, in reality, there is much here