Has Shown or Showed?

The past participle shown was uncommon before the 19th century, but is now the preferred form in standard English. In the UK, showed is regarded as archaic or dialectal. In the US, it is considered a standard variant form, but shown is more common.

Is has shown correct?

When is it appropriate to use each one? A: The usual past participle of “show” (that is, the form of the verb used with “had” or “have”) is “shown.” But “showed” is also acceptable and not a mistake. Dictionaries these days consider both of them standard English, but list “shown” first.

What is the difference between has shown and showed?

The rules of phrasal verbs apply the same for "show" as any other verb. To use "show up" using past perfect, you'd say "she has shown up" just like if you were saying "she has shown" but with "up" added afterwards. You don't use "she has showed".