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fill someone or something up (with something)
to put as much as possible into someone or something. We filled him up with chili and crackers. We will fill up the basket with leaves. I will fill the basket up with flowers.
1. to become full. The creek filled up after the heavy rain yesterday. The rain barrel began to fill up during the storm.
2. to fill one's gas tank. I've got to stop and fill up. The gas tank is running low. We will fill up at the next little town.
1. To become full: The bucket filled up with rain. The train filled up quickly, so we had to stand in the aisle.
2. To cause something to become full: I filled up the sink with soapy water. We inflated the pool and filled it up with water.
3. To fill some vehicle with fuel: I said to the mechanic, "Fill it up!" You'd better fill up the car soon. If we don't fill up now, we could run out of gas.