Heat up

Heat up

Today I’m going to show you how to use the phrasal verb “heat up.” In short , it means “to get hotter.”

“Heat up” can be used in two ways. First, you can talk about something getting hotter. And second, you can talk about how you—or something else—make a thing hotter.

Let’s start with the first way: something that gets hotter, without specifying how or why.

A common way to use this is with temperature. I live in Mexico City, and we’re at about 2,200 meters above sea level , a high altitude . And right now, we’re in the warmest month of the year. In the morning, it’s nice and cool, maybe 18 degrees Celsius. But in the middle of the afternoon, it can be 30, 31, maybe 32 degrees.

So the weather gets hotter during the day. At around 1:00, here in Mexico City, you can say, “It’s starting to heat up.” Or, “it’s starting to heat up outside.”

That means, it’s getting hotter. It’s starting to heat up.

Your laptop can heat up. If you’re working with a laptop on your lap , and you’ve been using it for a while, you might notice the laptop getting warmer. So you might say, “my computer’s heating up.” Now, it’s not dangerous —it’s not going to start a fire from normal use. But you might notice it getting a little hotter. It might be a little uncomfortable on your lap. “It’s starting to heat up.”

A handheld drill —or so I have read! I have no personal experience—but a handheld drill might heat up after you use it to drill through some thick boards .

A lot of physical and industrial processes use heat. A heat pump , for example, blows cold air over a chemical refrigerant. The refrigerant heats up a little—it gets a little hotter—and turns to gas. The pump then compresses the gas. And because it’s compressed, the metal coils heat up even more—they get really hot. That’s how a heat pump works .

The other way to use “heat up” is similar. But this way is to talk about someone or something acting to make something else hotter. You use this with a direct object. If you make coffee, then get distracted , and an hour later you take a sip —it’s cold. You might want to heat the coffee up in the microwave . You heat it up in the microwave: you take action to make the coffee hotter.

A hot tub can be therapeutic on a cool day. If you have a hot tub, you might want to heat the water up for a while before you get in. You take action to make the water hot.

I cook a lot; I cook most of my own meals. The other day I made stuffed peppers . The oven was at about 200 degrees Celsius. That started to heat up my kitchen, especially since I put the peppers in the oven mid-day, when the kitchen was already pretty warm. In this case, the oven took the action : the oven heated up the kitchen.

I’ll give you a quick tip. This is similar to “warm up.” You would use “warm up” if you want to make something hotter…but not too hot. If you start your car on a cold day, you’ll turn the heat on inside. You want the inside to warm up. You don’t want it to be hot in there. You just want it to be warm.

You might want to heat up coffee, so that it’s hot. But you might want to just warm up a slice of apple pie —you don’t want apple pie to be piping hot . So you’d warm that up.

See you next time!

Warm up or heat up? Which is which? Try it for yourself in the practice area. Think of your own examples, think of your life. Write an example that uses “heat up” or “warm up” or both and I’ll take a look for you. That’s in the area called “Your Turn” at PlainEnglish.com/682.

You write your sentence using today’s expression. I’ll read it and review it, and give you some feedback.

That’s all for today’s Plain English. Coming up on Thursday: are we doing two science episodes in a row? We might be. Why did Beethoven go deaf ? There are clues in his hair. That’s coming up on Thursday. See you then.