Efter fikat känner hon sig pigg.

she

Breakdown of Efter fikat känner hon sig pigg.

• efter: after
• känna: to feel
• sig: herself

Questions & Answers about Efter fikat känner hon sig pigg.

Why does the verb come before the subject in “Efter fikat känner hon sig pigg”?

Swedish main clauses follow the V2 rule: the finite verb is in the second position. Since the sentence starts with an adverbial (Efter fikat = After the coffee break), the verb comes next, then the subject: Efter fikat + känner + hon + …
Without the fronted adverbial, you’d say: Hon känner sig pigg.
Wrong would be: Efter fikat hon känner sig pigg.

Why is the reflexive pronoun “sig” needed after “känner”?

Because känna sig is the standard way to say “feel (a certain way)” about oneself. Without the reflexive, känna usually means “to know (someone)” or “to feel/touch” something.

• Jag känner mig pigg.
• Du känner dig pigg.
• Han/Hon/Den/Det/De känner sig pigg(a).
• Vi känner oss pigga.
• Ni känner er pigga.
  “Hon känner pigg” is ungrammatical.

Could I say “Efter fikat är hon pigg” instead? What’s the difference?

Yes. Är pigg states her condition as a fact; känner sig pigg highlights her subjective feeling. Both are idiomatic here, with only a slight nuance difference.

Can I use “känns” instead, like “Hon känns pigg”?

You can, but it means “she seems/feels (to others) energetic,” i.e., how she comes across.

• Hon känns pigg = She seems energetic (to us).
• Hon känner sig pigg = She feels energetic (to herself).
  Also common: Det känns bra (It feels good).