1. When a base or suffix ends in silent <e>, drop the <e> before adding a suffix which begins with a vowel.

        Here are some suffixes that begin with a vowel:
        <-ed> <-er> <-ing> <-en> <-ous>
        1. When a base or suffix ends in <-ce> or <-ge>, keep the <e> when adding <-ous> or <-able>.

          Here is an example:
          change + able —> changeable
      2. The suffix <-ful> is not the word <full> — it only has one <l>.

        Please look very carefully at this example and figure out what has been done.
        help + ful —> helpful
        1. Remember that if <-ly> is added to a word ending in <-ful> , the word has two <l>s, as in helpfully and carefully.

      3. The 1+1+1 rule: In many bases of one syllable ending in one consonant with one vowel before it, double the final consonant before adding suffixes which begin with a vowel, such as <-ed>, <-er>, <-est>, or <-ing>.

        Look at these examples:
        rob + er —> robber
        run + ing + running
        1. NB: Remember that the final consonant is not doubled when it is preceeded by two vowels or another consonant, such as:

          feel + ing —> feeling
          halt + ing —> halting
        2. NB: Never double the final letters <w>, <x>, and <y>:

          snow + ed —> snowed
          box + ing —> boxing
          play + er —> player
      4. Words ending in <y>

        When a base ends in a consonant followed by a <y>, you change the <y> to <i> before adding a suffix such as:

        <-ed>, <-er>, <-est>, <-ment>, <-ly>, or <-age>
        Please look very carefully at this example and figure out what has been done.
        cry + ed —> cried
        1. If the letter before a final <-y> is a vowel, the <-y> doesn’t change when you add a suffix:

          play + ed —> played
        2. The <-y> doesn’t change before suffixes beginning with <-i>

          such as <-ing>: carry + ing —> carrying
        3. NB: When a base ends in <-y> and is preceded by a consonant, to make the plural you change the <y> to <i> before adding <-es>.

          Here is an example: lady + s —> ladies
          1. NB: Remember, for bases ending in a vowel and a <y> you keep the <y> before adding <s> to make the plural,

            as in:
            valley + s —> valleys
            toy + s —> toys