Spelling Rules Rules For Adding Suffixes – ed, er, est, ing, ful, ness, ly... Double Final Consonant - When adding a suffix beginning with a vowel to a word that ends with a vowel and a single consonant, double the final consonant before you add a suffix. Eg. hid - hidden, hit - hitting, hot - hottest, mad - madder, skip – skipped. Change the y to an i - If a base word ends in y and has a consonant before it, you will need to change the y to an i before you add a suffix. Eg. happy - happiest, happiness, happier. BUT when adding suffixes starting with i keep the base word y, e.g. carrying, crying, enjoying, playing. Drop the e - If a base word ends in an e, which is part of a split digraph, drop the e if the suffix begins with a vowel. E.g. hope – hoping, like – liked, (the e before the d is part of the suffix, not part of the base word). Keep the e if the suffix begins with a consonant. E.g. hope – hopeful, safe – safely. Exceptions are skiing, taxiing.