Likely is similar to Promising. Promising is a synonym of Encouraging. Encouraging is related to Helpful. Helpful is related to Cooperative. 
Author is a type of Person. Person is related to Gentleman. 
Likely <--SimilarTo--> Promising <--Synonym--> Encouraging <--RelatedTo--> Helpful <--RelatedTo--> Cooperative 
Author --IsA--> Person <--RelatedTo--> Gentleman 