"Base form,Simple past,past participle"分别是什么意思?

Base from,Simple past,Past participle各是什么意思? past participle是什么意思 Rewrite the sentences using the past participle form of the past perfect vs.simple past.Choose the correct verb form. simple past/ past progressive past simple Past participle 和 present participle 怎樣用? past tense,present tense,past participle present ,past,past participle ,present partici past participle怎么用啊? 区分adj.与past participle write the pase form and the past participle of the verbs