[help me]Date Type

I want to get to date type..
I want to get to between data from 1990-01-01 to 1991-12-31. Example
sql> desc s_emp;
id number(7) not null,
start_date date

I did

sql>select id,start_date
sql>from s_emp
sql>where start_date between 01-MON-90 and 31-DEC-91

I unsuccess.
help me .I hope to get to data from 1990/01/01 to 1991/12/31.

please... Received on Sat Jun 03 2000 - 00:00:00 CDT