I assume you are referring to the Old Covenant sacrifices.
The sin offering was the most important sacrifice. It made atonement for the person of the offender, whereas the trespass-offering only atoned for one special offence. The trespass-offering may be regarded as representing ransom for a special wrong, while the sin-offering symbolised general redemption.
Transgression is an act, process, or instance of transgressing: as a: infringement or violation of a law, command, or duty.
What part of China are you from? I spent a month in Yanchen north of Shanghi in the 90's.