Could is related to Cloud. Cloud is related to Ball. you are likely to find Ball in/at/on Sack. 
Remark is related to Excellent. Excellent is related to Superior. Superior is similar to Upper. 
Could <--RelatedTo--> Cloud <--RelatedTo--> Ball --AtLocation--> Sack 
Remark <--RelatedTo--> Excellent <--RelatedTo--> Superior <--SimilarTo--> Upper 