我不明白她为什么没打电话。

I'm baffled as to why she hasn't called.

《牛津词典》

我不明白她为什么没打电话。

I'm baffled why she hasn't called.

《牛津词典》

我不明白她为什么会死。

I don't see why she died.

youdao

.. I just don't--people don't like-- ... people would rather hate-- I don't know why it's something-- it wouldn't be a good movie theme, would it?

我不。。。人们不喜欢-,人们宁愿厌恶-,我不明白为什么-,那不是好的电影主题吗？

耶鲁公开课 - 金融市场课程节选

I don't understand why you'd want to take a pill to fix something that we know little about.

我不明白为什么你会愿意吃药片来治好一些我们甚至都不清楚的毛病。

对付压力的方法 - SpeakingMax英语口语达人

And I didn't understand why.

而且我不明白为什么。

哈佛公开课 - 幸福课课程节选