The groceries, "groceries," (plural) are the food that I buy at the market. 杂货（groceries）（复数）是我在超市买的食物。

We sometimes call a supermarket a grocery store,  我们有时把超市称杂货店，

a place that you buy groceries — buy food that you bring home and prepare and eat at home. 你购买杂货的地方——购买你带回去准备在家吃的食物。

I decided "to make pasta." So, "I preheat the oven to 375." 我决定“做意大利面”。因此，“我将烤箱预先加热到375华氏度”。

To preheat, "preheat," really means the same here as to heat, 预热（preheat），在这里和加热的意思相同，

but if you look at the instructions for making food, what we would call the recipe, "recipe," the recipe for making food, 但如果你参看食物制作指南，也就是我们所说的食谱（recipe），

usually it begins, if you are going to cooking something in the oven, by telling you to preheat the oven. 通常会这样开头，在烹饪食物之前先预热烤箱。

That just means to turn it on so that when you are ready, when it is hot, you can put the food in to cook. 这句话的意思就是把它打开，这样当你准备好了、它又是热的时候，你就可以把东西放在里面烹饪。

Pre, "pre," means before or to do something before. “Pre”的意思是“在……前面”或“做某事之前”。

So, "I preheat the oven to 375," in other words, 375 degrees Fahrenheit. 因此，“我将烤箱预先加热到375”，也就是375华氏度。