On Tue, 04 Mar 2014 15:55:51 -0500, Dave Smith
> wrote:

>On 2014-03-04 2:21 PM, Nancy2 wrote:
>> You are right about heating the oven anytime.
>>
>> Why not just say, "Heat the oven to 350 deg.F., and put your [food item] in." No need to say, "Pre-heat your
>> oven to 350 deg.F., and put your [food item] in."
>>
>
>
>Because...... telling people to preheat the oven tells them to turn it
>on to the prescribed temperature ahead of time.
>
Preheat seems more economical than saying "Before you start preparing
this dish, heat the oven."
Janet US