"So we're using up precious fuel, " Strambli said, frowning so hard she made her lopsided face even less symmetrical. "In order to get more fuel."

using up -->?use up -->?use

lopsided means not?equally?balanced

symmetrical means?having two?parts?that?match?exactly, either when one?half?is like an?image?of the other?half?in a?mirror, or when one?part?can take the?place?of another if it is?turned?90° or?180°

a?charming, lopsided?grin?迷人的撇嘴一笑

precious means?of?great?value?because of being?rare,?expensive, or?important