这份列表包含了100个以元音字母开头的英语名词，如“apple”，“egg”，“umbrella”等，这些名词前需要使用“an”。这份列表可以帮助你更好地掌握英语中名词的使用规则。
- an apple
- an egg
- an umbrella
- an orange
- an igloo
- an octopus
- an antelope
- an elephant
- an iguana
- an onion
- an omelette
- an otter
- an artist
- an oven
- an axolotl
- an oyster
- an avocado
- an owl
- an awning
- an ounce
- an axe
- an oasis
- an oatmeal
- an overcoat
- an oak tree
- an oboe
- an odometer
- an obelisk
- an office
- an olive
- an opera
- an opal
- an optic
- an option
- an orangutan
- an order
- an organ
- an orphan
- an orchid
- an ore
- an orca
- an oriole
- an oriental rug
- an origami
- an ostrich
- an otoscope
- an outlet
- an outlaw
- an oven mitt
- an ox
- an oxbow
- an oxygen mask
- an oxyacetylene torch
- an ounce scale
- an orange peel
- an orange blossom
- an orange juice
- an orbit
- an orchard
- an orchestra
- an organ grinder
- an overhang
- an ovary
- an owl pellet
- an owl hoot
- an owner
- an oil change
- an oil rig
- an oil tanker
- an oil spill
- an oil lamp
- an oil painting
- an oil refinery
- an oil field
- an oil well
- an oil drum
- an oil filter
- an oil slick
- an oil pump
- an oil can
- an oil pan
- an oil pressure gauge
- an oil skimmer
- an oil stain
- an oil platform
- an oil reserve
- an oil truck
- an oil pipeline
- an oil change
- an oil spill response boat
- an oil spill containment boom
- an oil spill response team
- an oil rig worker
- an oil tanker captain
- an oil well driller
- an oil field technician
- an oil refinery worker
- an oil platform engineer
- an oil truck driver
- an oil pipeline inspector
