Overdue

Overdue= (1) (of payment) past due; being unpaid by the assigned date or at the scheduled time: The electric bill was two months overdue.An overdue installment.

Be/become overdue is used of payments, library books, video films that you have rented etc.: Even if the books are only one day overdue, you still have to pay a fine.

Expire is used of a license, contract, membership card, etc.: I wanted to pay by visa, but my card has expired.I suddenly realized that my driving license had expired.

Outdoor

Outdoor (WITHOUT s) is an adjective. Outdoor = located, suited for, or taking place in the open air: He enjoys the outdoor life.There are many outdoor activities in and around  Coimbra.

Outdoors (WITH s) is an adverb. Outdoors = outside a building: He likes to work outdoors.

Outside = when you mean away from, use (get/go) out of (NOT outside): It does you good to get out of the city now and again.Without a passport, he would never have been able to get out of the country.

In British English, outside is not used with of: You aren’t allowed to park outside the bank.

In American English, both outside and outside of are used.

Originate

Originate = (1) come into existence; take on form or shape: The practice of  Sati originated during ancient Ages. (2) to give rise to; initiate: The policy was originated by the previous administration.(3) to create something new: Darwin originated the theory of evolution.

Originate is used in connection with things, ideas, customs etc. (NOT people): No one really knows how the solar system originated.

If you are born in and/or grow up in a particular place, town, country etc., you come from that place: Where does Agneta come from- Sweden or Norway?

Words that enter a language from other languages come from (or are derived from) those languages: The name terrier comes from the Latin word terra meaning the earth.

Oral

Oral = (1) using speech rather than writing: Always go for a written agreement in business than relying on an oral agreement.In the oral examination, she was asked to recite the name of all presidents. (2) of or relating to mouth: He has undergone an oral surgery.She practices good oral hygiene by brushing her teeth at least twice a day.

Both the words Spoken and Oral can be used to refer to language skills and the communication of information. However, oral is slightly more technical than spoken. The use of oral to mean spoken is restricted to certain technical phrases used in education: Oral skills, An oral examination.

Opposite

Use opposite and the opposite of only when you mean that two things are altogether different in nature, quality, or significance: thought that the medicine would make him sleepy, but it had the opposite effect.The opposite of long is short.The two men went off in opposite directions. (= one went to the left and one to the right)

To describe people opinions, life styles, ways of thinking etc., the usual word is different: These two schools of thought are completely different.

One thing is opposite another thing (WITHOUT to/of): The nearest bus stop is opposite the bank.

When opposite means facing the speaker or the person/place being talked about,it comes immediately after the noun: The house opposite is also for sale.

Operate

Operate = (1) direct or control something: Do you know how to operate this machinery? (2) perform surgery on (medicine): Have you heard what happened to the last patient he operated on? (3) to perform a function or work: The motor operates smoothly.The camera also operates underwater. (4) to be involved in military activities: A militant group  is operating against the government.

Operation = (1) the state of being in  effect or being operative: That law is no longer in operation. (2) a planned activity involving many people performing various actions: They planned a rescue operation. (3) a medical  procedure involving an incision with instruments: My mother is having an operation tomorrow. Mr. Barrett is going to have an operation on his back.

Once

Once = (1) one time only: You have to take this medicine once a day. (2) whenever; as soon as: Once it stops raining, we can go out. (3) at some indefinite time in the past: She was a very popular actress once. (4) used in negative sentences and questions, and after if to mean ever or at all: He didn’t once thank me.If she once decides to do something, it becomes difficult to change her mind.

Often

Often = (1) many times; frequently or in great quantities: The trains are often late.They often go out to dinner. (2) in many cases or instances: People are often afraid of things they don’t understand.

Every so often = sometimes; occasionally: I meet him at the club every so often.Every so often I heard a strange noise outside.

As often as not = quite frequently; usually; in a way that is typical of somebody/something: As often as not, he’s late for work.

Offence

Offence= (1) a feeling of anger caused by being offended: ‘He took offence at my slightest criticism.’ (2) the team that has the ball (or puck) and is trying to score: ‘Our team has the best offence in the league.’ Commit an offence (NOT do): ‘He is accused of committing various minor offences.’

O’clock

O’clock is a contraction of “of the clock” or “on the clock” that means “according to the clock”: ‘We are expected to be there at seven o’ clock in the morning.’

Do not use o’clock for times that include minutes or parts of an hour. Compare: ‘It’s four o’clock.’ ‘It’s ten past four.’

Use EITHER o’clock OR a.m./p.m. in a sentence (NOT both). Compare: ‘The work should be completed by seven o’clock.’ ‘The work should be completed by seven p.m.’

Do not use o’clock after 6.00, 7.00 etc. Compare: ‘8 a.m.’, ‘8.00’, ‘8.00 a.m.’, ‘8 o’clock’.