He opened the conference by linking scientific progress to Africa's development at large.

他在会议开幕式上将科学进步与整个非洲的发展联系起来。

In the treaty of alliance with France, the United States had promised that peace should be a joint affair agreed to by both nations in open conference.

在与法国的同盟条约中，美国承诺和平应该是两国在公开会议上同意的共同事务。