Grammer

Past participle (plural past participles)

(grammar) A participle indicating a completed action or state, and functioning as an adjective. When combined with the verb to have, a past participle forms the perfect tenses of a verb. In a regular verb, the past participle ends in -ed and has the same spelling as the past tense of the verb. Sometimes the last consonant needs to be doubled. Sometimes the end vowels change: y -> ied.

Usage notes
Remember to always use the past participle with an auxiliary verb: have, has, or had.

to love (loved) have/has/had loved
to ride (rode) have/has/had ridden
to construct (constructed) have/has/had constructed
to write (wrote) have/has/had written
to forget (forgot) have/has/had forgotten
to know (knew) have/has/had known
to strike (struck) have/has/had struck or have/has/had stricken
to eat (ate) have/has/had eaten
Notice how all of the endings are not the same. Some end in "-ed" like many preterite tense words, while irregular verbs tend to end in "-en". For other and more irregular verbs you may refer to the list of irregular verbs
Past tense (plural past tenses)

(grammar) Past tense is the form of language used to refer to an event, transaction, or occurrence that did happen or has happened, or an object that existed, at a point in time before now. Compare with present tense, which refers to an event, transaction or occurrence which is happening now (or at the present time), or an object that currently exists; or with future tense, which refers to an event, transaction or occurrence that has not yet happened, is expected to happen in the future, or might never happen.

past participle is when it is pass tense but also using present tense.
and pass tense is just pass tense I will give you examples.

Pass Participle: I am eating dinner at Tom's house yesterday. (eating is present tense but the sentence is still pass tense)
Pass Tense: Yesterday I went to Tom's house. (went to is pass tense)

Need more examples you can e-mail me. ( [email protected] )