Common Prefixes And Their Use In OET Writing

OET is a test of English and to be able to score higher in your OET, it is important to have good command over English. The content of the test is entirely medical in nature. Grammar, vocabulary, spelling matter a lot. Specially, your OET writing sub-test is a big challenge. Because, your written English is assessed based on a number of factors. 

In the OET listening test, an error in spelling may not affect your score (as long as it is based on the pronunciation or the sound of the word) but in the OET writing sub-test, it can lower down your score. 

Suppose, if you write pneumonia as a nemonia, it is still acceptable in OET listening sub-test but in writing test, this error in spelling will not be accepted. 

Similarly, prefixes in OET writing sub-test have great importance too. You can’t ignore them. 

In English language, prefixes are used to create the opposite of the words. Common prefixes are as follows: 

  • Il-
  • Im-
  • In-
  • Ir- 
  • Un- 

Take a look at the following words:

Movable, Reducible, Regular, Sanitary, Complete, Conscious, Operable, Palpable, Pure, Qualified, Dependent, Digested, Direct, Fertile, Fit, Healthy, Hygienic, Legal, Adequate, Controllable, Soluble, Stable, Well, Coherent, Compatible, etc. 


By adding Im (examples: immovable, impalpable, impure, etc. 

By adding Un (examples: undigested, unfit, unhealthy, unhygienic, unconscious, uncontrollable, unqualified, unstable, unwell, etc)

By adding In (examples: inactive, inadequate, indirect, infertile, inoperable, insanitary, incoherent, incompatible, incomplete, independent, etc.  

By adding Il (examples: illegal, irreducible, irregular, etc)

Example sentences:

  • The old man was found unconscious in the street.
  • He felt unwell so he went home.  
  • He has an uncontrollable desire to drink alcohol.  
  • What actually makes the poison incapable was the serum. 
  • Your child seems to have a very unhealthy diet. 
  • When the nurse noted that the patient had developed an irregular pulse, she immediately informed the doctor.  
  • He was unfit in the winter.  
  • The doctors informed her that the cancer was unpasteurized.  
  • Due to insanitary conditions in the town, the cholera spread.   
  • The patient is noted to have an unstable mental condition.  

Want to prepare for the OET? Enroll for the OET exam preparation online at OETPractice.net. 

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