Language Point 32

Falling into a sleeplike condition, he suddenly felt as though he were sinking in a mighty flood of water, ...(Para. 4)
Meaning : He seemed to fall into a sleeplike condition. Suddenly he felt as if he were sinking in a violent ocean.
as though: as if
Please note that "as though" or "as if" is often followed by a clause in subjunctive mood (虚拟语气).
Why is she looking at me as though she knew me? I have never seen her before in my life.

为什么她老看着我，好像认识我似的？我可从未见到过她呀。
She looks almost as if she were drunk.

她看上去像是喝醉了。
Please note the difference in the following two sentences:
You look as if you've been running. (The person may have been running.)

看来你像是刚跑过步。
You look as if you'd seen a spirit. (The person has probably not seen a spirit, but just looks shocked.)

看来你是见到鬼了。