Today’s phrasal verb, “blow up” has a few different meanings. Some of them you may know and some of them you may not. Let me go over the different meanings for you now.
1. to inflate something with air using one’s mouth. For example:
Can you help me with these balloons? I need to blow them up before the party starts.
I had to blow up an air mattress for my daughter, so I’m really out of breath now.
2. for someone to cause something to explode. For example:
Did you hear about what happened to the mayor’s car? Somebody blew it up yesterday! He was killed instantly.
The mayor’s car was blown up yesterday, and he died in the explosion. (passive voice)
On the TV show 24, people are constantly blowing things up.
Things are constantly being blown up on the TV show, 24. (passive voice)
3. for something to explode. (intransitive) For example:
The plane blew up after it crashed into the mountain.
There was a gas leak in my friend’s trailer, and it blew up. Luckily, no one was in it at the time.
4. to enlarge a photograph. For example
I can’t see the people in this picture very well. Can you blow it up for me?
We can blow this photo up a little, but if we do it too much, the image won’t be clear.
5. to lose one’s temper and get angry at someone. (usually used with “at” and is inseparable) For example:
My mom blew up at my dad yesterday when he came home drunk again.
I blew up at my friend yesterday after she kept me waiting for half an hour. I hate it when she’s late!
As I wrote above, the third meaning is intransitive, so it doesn’t take an object. The difference between the second meaning and the third one is that in the second meaning, somebody intentionally causes the explosion, but in the third meaning, the explosion happens naturally or we don’t know the cause of it.
With the fifth meaning, we use the preposition “at” after the phrasal verb. This means that the person gets angry directly when talking to another person. If we say, “I blew up at my friend.”, it means I got angry when talking to my friend and shouted at him or her.
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