Definition

Examples

• 恐龙在白垩纪末期灭绝了。
  Kǒnglóng zài Bái è jì mòqī mièjué le.
  Dinosaurs went extinct at the end of the Cretaceous period.
• 白垩纪的地层中含有大量石灰岩。
  Bái è jì de dìcéng zhōng hányǒu dàliàng shíhuīyán.
  The strata of the Cretaceous period contain large amounts of limestone.
• 科学家在白垩纪岩石中发现了新的化石。
  Kēxuéjiā zài Bái è jì yánshí zhōng fāxiàn le xīn de huàshí.
  Scientists discovered new fossils in Cretaceous rocks.