在常温下工作的零件，在发生弹性变形后，如果变形总量保持不变，则零件内的应力将保持不变。
参考答案：对
选出正确的词，并写在横线上。
1. —Have you ever been to Europe? —No, but I ______ (have been/went) to Africa last year.
2. —Have you ever been to my house? —No. But I'm coming to your party ______ (tonight/this night).
3. Has Victor ______ (been ever/ever been) to China?
4. In future, people will ______ (spend/waste) a long vacation every year.
5. He is an ______ (exchanged/exchange) student in this school.
战略规划
