English spelling can get rather tricky. It used to be much harder--the English language changed a lot after the Middle Ages in an event called the Great Vowel Shift. That was when we decided words like "Shoppe" should be spelled "Shop", or "Aprille" should be spelled "April." English still retains some of that old goofiness, though, as evidenced by how common misspellings are. Double letters, especially double consonants, tend to cause a lot of trouble. Other common culprits are exceptions to popular mnemonics, like how "weird" violates the commonly stated "i before e, except after c".
Here's a list of the most commonly used misspellings that occur in exams:
| 
 S.NO.  | 
 CORRECT SPELLINGS  | 
 COMMON INCORRECT SPELLINGS  | 
| 
 
 1.  | 
 
 absence  | 
 
 absense, absentse, abcense, absance  | 
| 
 2. 
  | 
 
 acceptable  | 
 
 acceptible  | 
| 
 3. 
  | 
 
 accidentally/accidently  | 
 
 accidentaly  | 
| 
 4. 
  | 
 
 accommodate  | 
 
 accomodate, acommodate  | 
| 
 
 5.  | 
 
 achieve  | 
 
 acheive  | 
| 
 
 6.  | 
 
 acknowledge  | 
 
 acknowlege, aknowledge  | 
| 
 
 7.  | 
 
 acquaintance  | 
 
 acquaintence, aquaintance  | 
| 
 
 8.  | 
 
 acquire  | 
 
 aquire, adquire  | 
| 
 
 9.  | 
 
 acquit  | 
 
 aquit  | 
| 
 10. 
  | 
 
 acreage  | 
 
 acrage, acerage  | 
| 
 11. 
  | 
 
 address  | 
 
 adress  | 
| 
 12. 
  | 
 
 adultery  | 
 
 adultary  | 
| 
 
 13.  | 
 
 advisable  | 
 
 adviseable, advizable  | 
| 
 
 14.  | 
 affect  | 
 effect  | 
| 
 15. 
  | 
 aggression  | 
 agression  | 
| 
 16. 
  | 
 aggressive  | 
 agressive  | 
| 
 
 17.  | 
 allegiance  | 
 allegaince, allegience, alegiance  | 
| 
 18. 
  | 
 almost  | 
 allmost  | 
| 
 19. 
  | 
 amateur  | 
 amatuer, amature  | 
| 
 
 20.  | 
 annually  | 
 anually, annualy  | 
| 
 21. 
  | 
 apparent  | 
 apparant, aparent, apparrent, aparrent  | 
| 
 
 22.  | 
 argument  | 
 arguement  | 
| 
 
 23.  | 
 atheist  | 
 athiest, athist  | 
| 
 
 24.  | 
 awful  | 
 awfull, aweful  | 
| 
 
 25.  | 
 becoming  | 
 becomeing  | 
| 
 26. 
  | 
 beginning  | 
 begining  | 
| 
 
 27.  | 
 believe  | 
 beleive  | 
| 
 
 28.  | 
 buoyant  | 
 bouyant  | 
| 
 29. 
  | 
 business  | 
 buisness  | 
| 
 30. 
  | 
 camouflage  | 
 camoflage, camoflague  | 
| 
 31. 
  | 
 cemetery  | 
 cemetary, cematery  | 
| 
 32.  | 
 changeable  | 
 changable  | 
| 
 33.  | 
 chief  | 
 cheif  | 
| 
 34. 
  | 
 
 colleague  | 
 
 collaegue, collegue  | 
| 
 
 35.  | 
 column  | 
 Column, colum  | 
| 
 
 36.  | 
 committed  | 
 commited, comitted  | 
| 
 
 37.  | 
 comparison  | 
 comparsion  | 
| 
 
 38.  | 
 concede  | 
 conceed  | 
| 
 
 39.  | 
 congratulate  | 
 congradulate  | 
| 
 
 40.  | 
 conscientious  | 
 consciencious  | 
| 
 
 41.  | 
 conscious  | 
 concious, consious  | 
| 
 42.  | 
 consensus  | 
 concensus  | 
| 
 43.  | 
 controversy  | 
 contraversy  | 
| 
 44.  | 
 coolly  | 
 cooly  | 
| 
 45.  | 
 daiquiri  | 
 dacquiri, daquiri  | 
| 
 46.  | 
 deceive  | 
 decieve  | 
| 
 47.  | 
 definite  | 
 definate, definit  | 
| 
 48.  | 
 definitely  | 
 definitly, definately, defiantly  | 
| 
 49.  | 
 desperate  | 
 desparate  | 
| 
 50.  | 
 difference  | 
 diffrence  | 
| 
 51.  | 
 dilemma  | 
 dilema  | 
| 
 52.  | 
 disappoint  | 
 dissapoint  | 
| 
 53.  | 
 disastrous  | 
 disasterous  | 
| 
 54.  | 
 drunkenness  | 
 drunkeness  | 
| 
 55.  | 
 dumbbell  | 
 dumbell  | 
| 
 56.  | 
 embarrass  | 
 embarass  | 
| 
 57.  | 
 equipment  | 
 equipmnt  | 
| 
 58.  | 
 exceed  | 
 excede  | 
| 
 59.  | 
 exhilarate  | 
 exilerate  | 
| 
 60.  | 
 existence  | 
 existance  | 
| 
 61.  | 
 experience  | 
 experiance  | 
| 
 62.  | 
 extreme  | 
 extreem  | 
| 
 63.  | 
 fascinating  | 
 facinating  | 
| 
 64.  | 
 fiery  | 
 feiry  | 
| 
 65.  | 
 fluorescent  | 
 flourescent  | 
| 
 66.  | 
 foreign  | 
foriegn | 
| 
 67.  | 
 friend  | 
 freind  | 
| 
 68.  | 
 fulfil  | 
 Fulfil, fulfill  | 
| 
 69.  | 
 gauge  | 
 Gaug, guage  | 
| 
 70.  | 
 grateful  | 
 gratefull, greatful  | 
| 
 71.  | 
 guarantee  | 
 garantee, garentee, garanty  | 
| 
 72.  | 
 guidance  | 
 Guidance  | 
| 
 73.  | 
 harass  | 
 harrass  | 
| 
 74.  | 
 height  | 
 heighth, heigth  | 
| 
 75.  | 
 hierarchy  | 
 heirarchy  | 
| 
 76.  | 
 humorous  | 
 humerous  | 
| 
 77.  | 
 hygiene  | 
 hygene, hygine, hiygeine, higeine, hygeine  | 
| 
 78.  | 
 ignorance  | 
 ignorence  | 
| 
 79.  | 
 imitate  | 
 immitate  | 
| 
 80.  | 
 immediately  | 
 imediately  | 
| 
 81.  | 
 indict  | 
 indite  | 
| 
 82.  | 
 independent  | 
 independant  | 
| 
 83.  | 
 indispensable  | 
 indispensible  | 
| 
 84.  | 
 inoculate  | 
 innoculate  | 
| 
 85.  | 
 intelligence  | 
 inteligence, intelligance  | 
| 
 86.  | 
 leisure 
  | 
 liesure  | 
| 
 87.  | 
 liaison  | 
 liason  | 
| 
 89.  | 
 library  | 
 libary, liberry  | 
| 
 90.  | 
 license  | 
 lisence  | 
| 
 91.  | 
 lightning  | 
 lightening  | 
| 
 92.  | 
 maintenance  | 
 maintainance, maintnance  | 
| 
 93. 
  | 
 marshmallow  | 
 Marshmellow  | 
| 
 
 94.  | 
 medieval  | 
 medeval, medevil, mideval  | 
| 
 
 95.  | 
 millennium  | 
 millenium, millennium  | 
| 
 
 96.  | 
 miniature  | 
 miniture  | 
| 
 
 97.  | 
 Minuscule  | 
 miniscule  | 
| 
 
 98.  | 
 mischievous  | 
 mischievious, mischevous, mischevious  | 
| 
 
 99.  | 
 misspell  | 
 mispell, misspel  | 
| 
 100.  | 
 necessary  | 
 neccessary, necessery  | 
| 
 101.  | 
 niece  | 
 neice  | 
| 
 102.  | 
 noticeable  | 
 noticable  | 
| 
 103.  | 
 occasion  | 
 occassion  | 
| 
 104.  | 
 occasionally  | 
 occasionaly, occassionally  | 
| 
 105.  | 
 occurrence  | 
 occurrance, occurence  | 
| 
 106.  | 
 omission  | 
 ommision, omision  | 
| 
 107.  | 
 outrageous  | 
 outragous  | 
| 
 108.  | 
 parliament  | 
 parliment  | 
| 
 109.  | 
 pastime  | 
 passtime, pasttime  | 
| 
 110. 
  | 
 perceive  | 
 percieve  | 
| 
 111.  | 
 perseverance  | 
 perseverence  | 
| 
 112.  | 
 Personnel  | 
 personell, personel  | 
| 
 113.  | 
 Plagiarize  | 
 plagerize  | 
| 
 114.  | 
 playwright  | 
 playright, playwrite  | 
| 
 115.  | 
 ossession  | 
 posession, possession  | 
| 
 116.  | 
 precede  | 
 preceed  | 
| 
 117.  | 
 presence  | 
 Presence  | 
| 
 118.  | 
 privilege  | 
 privelege, priviledge  | 
| 
 119.  | 
 professor  | 
 professer  | 
| 
 120.  | 
 protester  | 
 protestor  | 
| 
 121.  | 
 promise  | 
 promiss  | 
| 
 122.  | 
 pronunciation  | 
 pronounciation  | 
| 
 123.  | 
 proof  | 
 prufe  | 
| 
 124.  | 
 publicly  | 
 publically  | 
| 
 125.  | 
 quarantine  | 
 quarentine  | 
| 
 126.  | 
 questionnaire  | 
 questionaire, questionnair  | 
| 
 127.  | 
 readable  | 
 readible  | 
| 
 128.  | 
 receive  | 
 recieve  | 
| 
 129.  | 
 recommend  | 
 recomend, reccommend  | 
| 
 130.  | 
 referred  | 
 refered  | 
| 
 131.  | 
 Reference  | 
 referance, refrence  | 
| 
 132.  | 
 Relevant  | 
 relevent, revelant  | 
| 
 133.  | 
 Religious  | 
 religous, religius  | 
| 
 134.  | 
 Repetition  | 
 repitition  | 
| 
 135.  | 
 Restaurant  | 
 restarant, restaraunt  | 
| 
 136.  | 
 rhythm  | 
 rythm, rythem  | 
| 
 137.  | 
 secretary  | 
 secratary, secretery  | 
| 
 138.  | 
 seize  | 
 sieze  | 
| 
 139.  | 
 separate  | 
 seperate  | 
| 
 140.  | 
 sergeant  | 
 sargent  | 
| 
 141.  | 
 similar  | 
 similer  | 
| 
 142.  | 
 Skilful  | 
 skilfull  | 
| 
 143.  | 
 speech 
  | 
 speach, speech 
  | 
| 
 144.  | 
 successful 
  | 
 succesful, successfull, sucessful 
  | 
| 
 145.  | 
 supersede 
  | 
 supercede 
  | 
| 
 146.  | 
 surprise 
  | 
 suprise, surprize 
  | 
| 
 147.  | 
 than 
  | 
 Then, thane, thene 
  | 
| 
 148.  | 
 tomatoes 
  | 
 tomatos 
  | 
| 
 149.  | 
 tomorrow 
  | 
 tommorow, tommorrow 
  | 
| 
 150.  | 
 twelfth 
  | 
 twelth 
  | 
| 
 151.  | 
 tyranny 
  | 
 tyrany 
  | 
| 
 152.  | 
 underrate 
  | 
 underate 
  | 
| 
 153.  | 
 until 
  | 
 untill 
  | 
| 
 154.  | 
 upholstery 
  | 
 upholstry 
  | 
| 
 155.  | 
 usable/useable 
  | 
 usible 
  | 
| 
 156.  | 
 vacuum 
  | 
 vaccuum, vaccum, vacume 
  | 
| 
 157.  | 
 vehicle 
  | 
 vehical 
  | 
| 
 158.  | 
 vicious 
  | 
 visious 
  | 
| 
 159.  | 
 weather 
  | 
 wether, whether 
  | 
| 
 160.  | 
 Weird 
  | 
 wierd 
  | 
| 
 161.  | 
 welfare 
  | 
 wellfare, welfair 
  | 
| 
 162.  | 
 whether 
  | 
 Wether 
  | 
| 
 163.  | 
 wilful 
  | 
 Wilfull 
  | 
| 
 164.  | 
 withhold 
  | 
 withold 
  | 
| 
 165.  | 
 writing 
  | 
 writting, writeing 
  | 
| 
 166.  | 
 which 
  | 
 Wich, witch 
  |