1. Who is the scientist firstly find radium? 首先发现镭的科学家是谁?
2. Now we firstly discuss the infection phase. 首先,我们先来讨论感染阶段。
3. Firstly, no accomplishment can be achieved in a short time, and success asks for continuous industrious work and efforts. 第一,没有任何成就是可以在短时间内达到的,而是需要持续的勤奋工作和努力。