Example 1
We deduced that the fish tank had exploded while we were at the movies.
In this example, we add the helping verb had to the regular past participle exploded to make the past perfect. Remember, for regular verbs, the past simple form and the past participle form look exactly the same.
Example 2
We have thrown all of the toilet paper rolls in the Wulf family's trees. Let's get out of here!
Check it out: adding the helping verb have to the irregular past participle thrown creates the present perfect tense in this sentence. In other words, the speaker's saying, "Ladies and gentleman, at present we have dispensed with all of our rolls of Charmin. To the getaway coach!"
Example 3
Greg will have eaten a dozen funnel cakes before he leaves Six Flags tonight.
In this stomach-churning sentence, we've added the helping verbs will and have to the irregular past participle eaten to create the future perfect tense. After eating all of those funnel cakes, we're willing to bet ol' Greg will be feeling significantly less than perfect at the end of the night.