I have a question about this form そうな/そうに


> ねむくなってしまい **そうに** 癒される。

I can't figure out what this sentence is saying. I've asked my girlfriend and
my coworkers (both Japanese) about そうに and they can't explain it. (One of my
coworkers said it means 'a/an' but I can't see it being that. I've looked
around online but have only found そうにもない。




そうに is the continuous form of the verbal auxiliary そうだ which indicates manner
and mood. For example:

> 美味し **そうに** 食べる。 -- You eat foods with keen relish.  
>  この車は速 **そうだ** 。 -- This car looks fast.

I feel ねむくなってしまいそうに癒される is a bit unnatural, and ねむくなってしまうほど癒される (I am so
comforted that I become sleepy) would be more natural.

