on second thoughts /θɔːt/ (noun) Example: I thought I'd go to the movies, but on second thought I'd rather stay home.
out of date /ˌaʊt əv ˈdeɪt/ (adjective) old-fashioned or without the most recent information and therefore no longer useful Example: This rotary telephone is out of date.
out of reach /aʊt ɑv riːtʃ/ (phrase) Example: Place the cookies out of reach, or the children will eat them all.
out of danger /aʊt ɑv ˈdeɪn·dʒɚ/ (phrase) Example: Doctors said the woman, who was bleeding heavily when brought in by an ambulance, was now out of danger.
out of use /aʊt ɑv ju Example: This laptop is out of use because it was broken.
out of the question /ˈkwestʃən/ (noun) Example: His success is out of the question.
out of order /ˈɔːrdər/ (noun) Example: The washing machine is out of order and won't be repaired until tomorrow.
under control /ˈʌn.dɚ kənˈtroʊl/ Example: We finally got things under control and functioning smoothly.
under cover /ˈʌndɚ ˈkʌv·ɚ/ Example: These foxes come out only at night, under cover of darkness.
out of work /ˌaʊt əv ˈwɜːrk/ (adjective) unemployed Example: He lost his job a year ago and has been out of work ever since.
by mistake /baɪ mɪˈsteɪk/ (phrase) Example: I made a wrong calculation by mistake.
on the contrary /ɑːn ðə ˈkɑːn.tre·ri/ (phrase) Example: I thought he was busy, but on the contrary he was idle.
on average /ɑːn ˈæv.ɚr.ɪdʒ/ (phrase) Example: The average age of the students in this program is about 23 years old.
on one’s own /ɑːn wʌn's oʊn/ (phrase) Example: At present he lives on his own and the world is nothing to him.
on purpose /ɑːn ˈpɝː.pəs/ (phrase) Example: Someone poured wine on my laptop on purpose.
on time /ɑːn tɑɪm/ (phrase) Example: Please be sure to come on time.
on fire /ɑːn faɪr/ (phrase) Example: That house on the corner is on fire!
on and off /ɑːn ənd ɔf/ (phrase) Example: We've been working on the garden all summer, on and off.
by chance /baɪ tʃæns/ (phrase) Example: I met her by chance on a train.
within reach /wɪθˈɪn riːtʃ/ (phrase) Example: We were within reach of the finish line.