Struggling in the Knowledge level

I have been reading this paper for the recent 3 days. It is difficult for me.

Maybe I printed the paper in too small size font; maybe it is written in ancient English(^_^); maybe a 40 pages article is too long; maybe my understanding is too far behind Allen Newell; maybe it is not a good time for study, I mean in
Tokyo it's hot and sweet all day;...

I have tried to find all kinds of excuses, while struggling finished it. With
little inspirations. But, yes, I will try to read again, after some Japanese study.

My target is : to gain a better understanding of konwledge.
Wikipedia again will help me.
This paper is valuable to me, not because it is written by Allen Newell, but because seemingly it is the foundation of ontology (Gruber, T. R. (1993). A Translation Approach to Portable Ontology Specifications. konwledge acquisition, 5(2),199-220)