Something that is typical is characteristic or distinctive of a certain type or specimen. Something that is quintessential is not only characteristic or distinctive of a type, but goes a step further to capture the pure and essential essence of it—or to embody it perfectly. Quintessential is used to talk about people or things that are exactly as one might imagine or hope for them to be, based on widely circulated and understood ideas or ideals.
To safeguard something is to guard, protect, or secure it. Often this term suggests taking forceful measures to ensure something does or does not happen. As a result, the term conveys a degree of assurance that the safety of something is guaranteed. Safeguard is more likely to be used of ideas or concepts—immaterial things—than it is of property or physical objects. For instance, you’re more likely to hear of a leader or governing body taking measures to safeguard the rights of a specific group than to safeguard a wetland, the latter being better suited for use with the verb protect.
To corroborate something is to make more certain of it with evidence. In a courtroom, witnesses might be called to corroborate a story put forth by a defendant. Early findings in scientific research might be corroborated by additional scholarly work or laboratory results. More broadly, corroborate means “to strengthen”—and since this term's debut in English in the first half of the 16th century, it has been used to refer to strengthening or reinforcing things materially, to strengthening the health of things or people, and to strengthening a claim or statement.