O字母开头的单词或词组(第9页)：
- older
- Oct.
- out of style
- on the one hand
- on the other hand
- open up
- on board
- overseas
- optometrist
- Oxford
- Oxford University
- on display
- oversleep
- on the right
- on vacation
- OK
- on sale
- outer space
- organized
- obviously
- on time
- operation
- online
- overall
- on the phone
- others
- open day
- oyster
- on foot
- ozone
- orphanage
- octopus
- oval
- offering
- on end
- one another
- oops
- oriental
- over there
- out of
- onto
- outing
- of course
- outdoor