TY  - BOOK
AU  - Conrad,Susan
AU  - Biber,Douglas
AU  - Leech,Geoffrey N .
TI  - Longman student grammar of spoken and written English: workbook 
U1  - 421.5 C754l 2002 
PY  - 2002///
CY  - Essex
PB  - Pearson Education, 
KW  - INGLES
KW  - GRAMATICA
KW  - PROBLEMAS, EJERCICIOS, ETC
N2  - 5th impr.: 2005
ER  -