在那之后，我是那么恐惧以至于，以致我几乎不能清晰的思考了用英语怎么说

After that, I'm so feared that can hardly think clearly.
After that, I'm too feared to think clearly.
After that, I'm so feared that almost cannot think clearly.
用了现在时，是考虑到说话时可能仍处于这种状态。如果不是，仅是过去，那时态相应变为过去时就可以了。