Research shows that it is necessary to use the past participle in the past tense

No need. The past tense is used to express the meaning of verbs such as "past" and "finished". In Chinese, when expressing the time of an action, the method of adding words before and after the verb is used, that is, adding words before or after the verb, such as expressing "done" and "done" , just add "passed" and "finished" after the verb, such as eaten or seen. In English, the method of transformation is used, that is, no words are added, but the verb itself is changed. For example, eat becomes ate, see becomes saw. ate and saw are the past tense expressions of "eat" and "saw". . The "past participle" is a completely different matter. Its writing method is sometimes the same as the past tense and sometimes different (simple words are mostly different, long words are mostly the same), but its usage is completely different. It sometimes expresses "being..." ", sometimes used to express "complete...", can not only be used as a verb, but also as an adjective. The naming of "past participle" is extremely wrong and irresponsible. You cannot name it past tense just because it looks similar to the past tense. Such naming will cause unnecessary confusion and difficulty in distinguishing. In fact, if the past participle is renamed "passive" Participle" or "perfect participle" are easier to understand.