已知xl和x2是一元二次方程x2-3x-1=0的两根，那么x1x2=______．
∵a=1，c=-1，∴x1x2=ca=-1．
One of my ______ is ______ at the famous music school. [ ]
A. dream; studying
B. dreams; studying
C. dreams; to study
D. dream; studies
Mr Wang was born June 15th, 1977 Hefei. [ ]
A. on; in
B. in; in
C. in; on
D. on; on
