若x+y=9且xy=16，求x2+y2．
解：x2+y2
=（x+y）2﹣2xy
=92﹣2×16
=49．
支票的提示付款日期为出票之日起1个月。（ ）
. I think Ma Linlin will ____ a good monitor, so I'm going to vote for her.
A．remain
B．make
C．get
D．grow
