Of course. If we aren’t enlightened, chances are we are going to break the precepts sometimes. If we are just beginning to follow the precepts, then for sure we are going to break them sometimes. That’s why it’s called training.
What we don’t want to break is our refuge in the Triple Gem. If that happens then we loose all the protection of the whole practice.
If we do realize we have broken a precept, then we immediately make the determination to keep it in the future. We can wisely reflect on how it happened and the mental state we were in. We don’t obsess over it. We just determine to try and do things differently in the future. This determination is a hugely powerful factor in developing our mind.
In fact, this is why many Buddhists take the precepts on their own once or twice a day.
- Middle Length Discourses, sutta 61, Ambalatthika-rahul-ovada Sutta.