Place the carrots into the slow cooker first, followed by the onions. Use a 4-quart (4-liter) crock pot, at minimum. A 5- to 6-quart (5- to 6-liter) slow cooker would be even better. You need enough space for the lid to sit securely on the cooker, but the crock pot must be at least halfway filled. Use tongs to move the roast from the skillet to the slow cooker, sitting it directly on top of the vegetables. Pour the beef broth and Worcestershire sauce combination over the roast. Make sure that it wets the roast and also sinks down into the carrots and onion. The roast should cook for 8 hours on low. If you're running short on time, cook the roast for 4 to 5 hours on high, instead. Once the cooking time has passed, stick a meat thermometer into the thickest part of the roast. The temperature should be at least 165 degrees Fahrenheit (74 degrees Celsius). Use a sharp serrated knife and large fork to cut the roast into slices.  Serve the onions and carrots on the side. Keep warm until ready to serve.

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Write a summary of the previous text in Chinese:
在慢炖锅中铺上胡萝卜和洋葱。 将肉放进锅里。 将汤汁倒入锅里。 盖上盖子，炖肉。 检查肉的温度。 将肉和菜从锅里取出来。