Why do I believe in certain planets too far away to be observed directly through a telescope?

我为什么会相信在望远镜正常观测范围外的,遥远之处存在行星

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Or perhaps, you could be trying to explain that you don't know whether you can do something or not by a certain date.

又或者，你正在试图解释你没法确定你是否能在一个指定日期前做完某件事。

I don't know 课堂 - SpeakingMax英语口语达人