用所给单词的适当形式填空 1.Thomas Edison was a great American __________(invent). He had more than one thousand __________(invent) in his life. 2. A sweater is used for __________(keep) warm. 3. What are the __________(brush) made of? 4. Jim was seen __________( go) out of the room. 5. Today nylon can __________( find) in many things.