When does the suffix -ed indicate a past tense form?

The suffix -ed is used to form the past tense of regular verbs in English. When this suffix is added to a base verb, it typically indicates that the action occurred in the past. The condition of following a consonant is significant because most regular verbs that take -ed to indicate the past tense end in a consonant rather than a vowel. For example, "walk" becomes "walked," and "jump" becomes "jumped." This is crucial in understanding how the past tense forms work in conjunction with regular verbs.

In contrast, the application of -ed does not strictly rely on the preceding letter being a vowel since many verbs that take -ed end with a consonant. Note that irregular verbs do not adhere to this pattern and form their past tense differently, which is why the relation to irregular verbs is not applicable in this context. Additionally, the suffix -ed does not exclusively appear at the end of verbs, as there can be exceptions depending on sentence structure and verb form. Therefore, the indication that -ed appears following a consonant in regular verbs is a key aspect of its function in denoting the past tense in English.