About: http://webisa.webdatacommons.org/4530927

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	My principal difficulty is about when I must use in, on, at, about, to, for, with, -ing forms and other words or when not use them.
http://www.w3.org/ns/prov#wasQuotedFrom	usingenglish.com