1. 尽管我学习不好，但我从未放弃过。
    ________ I didn't do well in my lessons, I _______ gave up.
2. 鲍勃将跳远的世界纪录保持了多久？
    How long did Bob ________ the world _______ in the long jump?
3. 听到那悲伤的消息，他忍不住哭了。
    He couldn't _______  _______ when he heard the sad news.
4. 当我到达火车站时火车已经开走了。
    The train _______  _______ when I got to the train station.
5. 如果每个人都能为保护环境做出自己的贡献，这个世界将变得更加美好。
    The world will become much more beautiful if everyone _______ a contribution to _______ the environment.