My learner dictionary

1.Probation (n) :-a system that allows some criminals not to go to prison or to leave prison, if they behave well and see a probation officer regularly, for a particular period of time .
                         -a period of time, during which an employer can see if a new worker is suitable.
     -He pleaded guilty and was placed on probation.
     -a three month probation period
2.Treatment (n) :-medical -something that is done to cure someone who is injured or ill 
                            -behavior towards someone -a particular way of behaving towards someone or of dealing with them
     -There have been great advances in the treatment of cancer.

      -The best treatment for a cold is to rest and drink lots of fluids.

      -Some of the patients had to wait weeks to get the treatment they needed 

      -Civil rights groups have complained about the harsh treatment of prisoners.

3. incidental (adj) :-happening or existing in connection with something else that is more important.

    incident (n) :-an event, especially one that is unusual, important, or violent.

      -Increased motivation is more than an incidental benefit of reward schemes.

      -Am I at risk because of some incident in my sexual past?

4. circumstance (n) :-the conditions that affect a situation, action, event etc 

      -I can't imagine a circumstance in which I would be willing to steal.

      -The rules can only be waived in exceptional circumstances.

      -Prisoners can only leave their cells under certain circumstances.

5. collapse (v,n) :-decrease in structure , illness/injury , price , fail . It always take bad mean , and suddenly. 

      -Uncle Ted's chair collapsed under his weight.

      -He collapsed with a heart attack while he was dancing.

      -I thought that without me the whole project would collapse.

      -There were fears that property prices would collapse. 
 6. particular (n) - especially
                            - the facts and details about a job, property, legal case etc
                      (adj) -a particular thing or person is the one that you are talking about, and not any other
                             - special 
Most students choose one particular area for research.
You should pay particular attention to spelling.
It was a good concert - I enjoyed the last song in particular.
You may be required to give particulars of the change in your financial position.
 7. vulnerable (adj) -someone who is vulnerable can be easily harmed or hurt:
Children are most vulnerable to abuse within their own home.
We work mainly with the elderly and other vulnerable groups.
 8. reaction (n) - something that you feel or do because of something that has happened or been said ( response ) 
                         - your ability to move quickly when something dangerous happens suddenly:
                          -if you have a reaction to a drug or to something you have eaten, it makes you ill
The news brought an angry reaction from unions.
There were mixed reactions (=different people reacting in different ways) to the strike.
a skilled driver with very quick reactions
if you have a reaction to a drug or to something you have eaten, it makes you ill
 9. maintenance (n) -the act of making a state or situation continue
                              -the repairs, painting etc that are necessary to keep something in good condition
The purpose of the UN is the maintenance of international peace and security.
Engineers are carrying out essential maintenance work on the main line to Cambridge.
 10. sufficient ( adj) - as much as is needed for a particular purpose  ( enough ) 
We can only prosecute if there is sufficient evidence.
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