结束 终 and 完 all mean finish in english, just like how do you differentiate "finish", “end” and "over", they have the same meaning in single word, but should match different words or use in different occassion. For instance, “终” 一般在 “剧终” 和 “终于”等词语中用,你却不能说成 “剧完”或者“剧结束”, 如果要用这两个词表达同样意思,你可以说成-----“电视剧演完了' 或者 "电视剧结束了", 意思上就等同于”剧终“。 明白了吗?