1. To add a suffix like ed, ing, er, and est, that begin with a vowel to a word ending with a consonant simply double the final consonant when the last syllable is stressed and join the suffix.

Examples

Beg + ed = Begged	Begin + ing = Beginning
Run + ing = Running	Permit + ed = Permitted
Rob + er = Robber	Occur + ed = Occurred
Sad + est = Saddest	Control + er = Controller

The consonant is not doubled if the last syllable is not stressed.

Example

Benefit + ed = Benefited

Suffer + ing = Suffering

Exceptions (In the following words although the last syllable is not stressed the final consonant is doubled.)

Worship + ed = Worshipped	Handicap + ed = Handicapped
Kidnap + er = Kidnapper



2. If the last consonant is l then it is doubled even if the stress does not fall on the last syllable.

Examples

Quarrel + ed = Quarrelled	Signal + ing = Signalling
Travel + er = Traveller	Distil + er = Distiller

Exception (The l is not doubled)

Parallel + ed = Paralleled



3. When a word is ending with ll and the suffix ful is added to it, the second l is dropped.

Examples

Skill + ful = Skilful

Will + ful = Wilful



4. In the case of words ending in a silent e (the e is not pronounced), the e is dropped before the suffix beginning with a vowel.

Examples

Live + ing = Living	Move + ed = Moved
Hope + ing = Hoping	Drive = er = Driver



5. In the case of words ending in a silent e, the e remains where the suffix begins with a consonant.

Examples

Hope + ful = Hopeful

Engage + ment = Engagement

Exceptions (here the e is removed in spite of the suffix beginning with a consonant)

True = ly = Truly	Whole + ly = Wholly
Due = ly = Duly	Nine + th = Ninth
Argue + ment = Argument	Awe + ful = Awful



6. In the case of words ending with ce or ge , the e is retained when adding able and ous. In such words the c and g are pronounced soft before e and sometimes the e is retained to avoid confusion with a similar word.

Examples

Notice + able = Noticeable	Courage + ous = Courageous
Change + able = Changeable	Singe + ing = Singeing (to differentiate from singing)
Peace + able = Peaceable	Swinge + ing = Swingeing (to differentiate from swinging)



7. In the case of words ending with ee the e is not dropped before the suffix.

Examples

See + ing = Seeing

Agree + ment = Agreement



8. In the case of words ending in ie, the ie changes into y before the suffix.

Examples

Die + ing = Dying	Tie + ing = Tying
Lie + ing = Lying



9. In the case of words ending with y after a consonant, the y changes to i before the suffix when the suffix is not ing.

Examples

Happy + ly = Happily	Carry + ed = Carried
Beauty + ful = Beautiful	Marry + age = Marriage

Where the suffix is ing the y does not change.

Examples

Carry + ing = Carrying

Marry + ing = Marrying



10. In the case of words ending with y after a vowel, the y does not change before the suffix.

Examples

Pray + ed = Prayed

Play + er = Player

Exceptions (here the y changes to i)

Pay + ed = Paid	Day + ly = Daily
Say + ed = Said	Gay + ly = Gaily
Lay + ed = Laid



11. In the case of words where ie or ei is pronounced ee as in deep, i comes before e except when it is after c.

Examples

Believe	Receive
Relieve	Receipt
Achieve	Device
Grieve	Deceit
Yield	Conceive
Field	Conceit

Exceptions

Seize	Surfeit
Weird	Counterfeit
Protein	Plebeian

Note:

We all know that the vowels in the English alphabet are a, e, i, o, u. The three words where the vowels come in the same order are abstemious, arsenious and facetious.