13
Index Identification
                    ---- Head sorting method
lHead: most important word syntactically and semantically.
ˇFilter is the head of coffee filter, oil filter, etc
lSimplex NPs (SNP) are identified instead of Complex NP (CNP)
ˇ“A form” and “cancer causing asbestos” are two SNP
ˇ“A form of cancer causing asbestos” is a CNP.
lNPs are sorted by head in terms of their significances (frequency)