delphi与access的parameters.ParamByName提示"insert into''语法错误

我在delphi中向access表中插入一行记录,提示"insert into''语法错误,请大家指点.

with adoquery3 do
begin
if Active then close;
SQL.Clear;
SQL.add(' insert into user1(departmentid,userid,name,pwd,explain,pic)');
sql.Add('value(:departmentid,:userid,:name,:pwd,:explain,:pic)');
parameters.ParamByName('departmentid').Value:=trim(combobox1.text);
parameters.ParamByName('userid').value:=trim(edit2.text);
parameters.ParamByName('name').value:=trim(edit3.text);
parameters.ParamByName('pwd').value:=trim(edit5.text);
parameters.ParamByName('explain').value:=trim(edit6.text);
//parameters.parambyname('pic').Assign(image1.picture.Graphic)

showmessage(sql.Text);
execsql;
showmessage('添加成功');
end;