In the News: Malignant Tumor

There is a news today that doctors at Massachusetts General Hospital have announced that Ted Kennedy has malignant brain tumor.
http://www.cnn.com/2008/POLITICS/05/20/kennedy.tumor/index.html

Remember these two words today:

Malignant Tumor - 恶性肿瘤
Benign Tumor - 良性肿瘤

In general, malignant tumors grow faster than benign tumors and are more likely to cause health problems.

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From now on, I'll try to post 2 to 3 medium-level-difficulty but commonly used words from news media each day. While I am learning it, interested you can learn along - come back everyday so you'll be able to command ~1000 new words each year. When you sitting in front of your TV watching news at nights, hopefully you'll remember that internuts posted these words today :-)

Some people have asked for methods to learn English, here you go...