单项选择题
| There is a factory near our school. Mr. Li has worked there (41) then. Last November we visited the factory. We arrived (42) a Saturday morning. Mr. Li welcomed us at the factory gate. He told us (43) about the factory. Mr. Li told us (44) the machines because they were dangerous. He was afraid we might hurt (45) In one corner we saw cutting machines. These machines cut big pieces of metal into small pieces. In (46) corner, we saw a big and (47) machine. It (48) different pieces of metal together. The workers there all (49) thick clothes and glasses. We had a good time in the factory and we (50) a lot of things. |