Spelling Rules for Adding "ed"
Introduction

Vowel = a sound we make when the breath flows out through the mouth freely, without being blocked. The English letters a, e, i, o, u are called vowels, because they represent such sounds.

Consonant = a sound we make that is not a vowel. The breath is somehow blocked on its way out of the mouth. For example, the sound b is made when breath flow is stopped with the lips. All the English letters which are not vowels are called consonants. These are: b, c, d, f, g, h, j, k, l, m, n, p, q, r, s, t, v, w, x, y, z.

Some verbs change their spelling when "ed" is added to them.

Verbs ending with
"consonant-vowel-consonant"

When a verb ends with a consonant-vowel-consonant, and we put STRESS on this sound in speech, we double the last consonant. Then we add ed.

In the following examples the consonant is in blue, the vowel is in green, and ed is in red. The STRESS is underlined.

stop	=>	stopp + ed	=>	stopped
plan	=>	plann + ed	=>	planned

But if we don't put STRESS on this sound in speech, then we simply add ed.

open	=>	open + ed	=>	opened
visit	=>	visit + ed	=>	visited
listen	=>	listen + ed	=>	listened
happen	=>	happen + ed	=>	happened

Verbs ending with "e"

When a verb ends with the letter e, we add only the letter d.

In the following examples the letter e is in purple, and the letter d is in red.

dance	=>	dance + d	=>	danced
smile	=>	smile + d	=>	smiled

Verbs Ending with "y"

When a verb ends with the letter y, and there is a consonant before it, the y changes into i. Then we add ed.

In the following examples the consonant is in blue, the part before ed is in green, and ed is in red.

try	=>	tri + ed	=>	tried
cry	=>	cri + ed	=>	cried
study	=>	studi + ed	=>	studied

When a verb ends with y, and there is a vowel before it, we simply add ed to the verb.

In the following examples the vowel is in orange, the part before ed is in green, and ed is in red.