To prepare in advance means to do something beforehand in order to be ready for a future event or situation. This can be expressed in Engpsh as "to pre-study" or "to pre-read."

Here are some example sentences using these phrases:

"I'm going to pre-study for my upcoming math test so that I'm not caught off guard." (我会提前预习数学考试，这样我就不会措手不及。)
"She always pre-reads the instructions before starting a new project." (她总是在开始新项目前提前阅读说明。)

The phrase "to prepare in advance" comes from the verb "to prepare," which means to make or get something ready for a specific purpose or situation. This verb is often used in relation to events or situations that require careful planning or organization, such as preparing for a test or a trip. Adding the adverb "in advance" emphasizes that the preparation is happening before the event or situation takes place, rather than at the last minute.