134. The interrogative adverb of manner or degree, related to the
interrogative pronoun "kiu", is "kiel", how, in what way, to what
degree:
Kiel oni vivas en tia aero? How do people live in such air?
Kiel afabla sxi estas! How amiable she is!
Mi miras kiel la batalo okazis, I wonder how the battle happened.
Kiel longe li pensis pri gxi? How long did he think about it?