Various forms of “precede” and “subsequent” are often confused with each other, but the two terms are opposites. To “precede” is “to come before”; “subsequent” means “following in time”:
Record albums preceded compact discs.
Decades can be devoted to the discovery and subsequent clinical development of a single drug.
“Precede” is also sometimes confused with “proceed,” which means to go forward:
When stuck on a particular exam question, proceed to the next question, then return to the difficult question if time allows.