A lump the size of a packet of cigarettes.我感觉这是一个短语（没有谓语），可是为什么在段落中当一句话存在呢？请老师指点

回答如下：

这是一个无谓语动词的分句。由于没有谓语，不能看做一个完整的句，只能当作短语看到。对前面名词（肿块）描述性的补充说明.

A lump the size of a packet of cigarettes

参考译文：大小尺寸和一包香烟差不多

Right in the middle of Brand new bright red carpet, there was a lump. A lump the size of a packet of cigarettes.

就在全新的大红色地毯中间，一个肿块，其大小尺寸跟一包香烟差不多。

以上句子来自下面文章

The job of repairing the carpet was done and it was time for a last cigarette. Eddie began tapping the pockets of his overalls, looking for the new packet of Marlboro he had bought that morning. It was not there.
It was as he swung around to look in his toolbox for the cigarettes that Eddie saw the lump (鼓包). Right in the middle of the brand new bright red carpet, there was a lump.A lump the size of a packet of cigarettes. 
“I’ve done it again!” said Eddie angrily. “I’ve left the cigarettes under the carpet!”
He had done this once before, and taking up and repairing the carpet had taken him two hours. Eddie was determined that he was not going to spend another two hours in this house. He decided to get rid of the lump in another way. It would mean wasting a good packet of cigarettes, nearly full, but anything was better than taking up the whole carpet and fitting it again. He turned to his toolbox for a large hammer. 
Eddie didn’t want to damage the carpet itself, so he took a block of wood and placed it on top of the lump. Then he began to beat the block of wood as hard as he could. He kept beating, hoping Mrs. Vanbrugh wouldn’t hear the noise and come to see what he was doing. It would be difficult to explain why he was hammering the middle of her beautiful new carpet… The lump was beginning to flatten out.
After three or four minutes, the job was finally finished. Eddie picked up his tools, and began to walk out to his car. Mrs. Vanbrugh accompanied him. She seemed a little worried about something.
“Young man, while you were working today, you didn’t by any chance see any sign of Armand, did you? Armand is my bird. I let him out of his cage, you see, this morning, and he’s disappeared. He likes to walk around the house, and he usually just comes back to his cage after an hour or so and gets right in. Only today he didn’t come back. He’s never done such a thing before, it’s most peculiar…”
“No, madam, I haven’t seen him anywhere,” said Eddie, as he reached to start the car.
And he saw his packet of Marlboro cigarettes on the panel, where he had left it at lunchtime…
And he remembered the lump in the carpet

回答如下：

  是句号。不是逗号。

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