HSK4级语言点+听力训练（对话模式）｜Intermediate Chinese Sentences and Grammar｜越听越清 ｜中国語会話｜中级汉语

[@mountaintag]

For No. 14, we have: 本来打算玩一个小时 = "I was going to play for one hour" The verb is 玩. The auxiliary ("helper") verb is 打算. I have found that, when an auxiliary verb is used, the past tense is marked with 本来 (and not with 了). So, I think that 我打算了玩一个小时 would be incorrect.