There were times when emigration bottleneck was extremely rigid and nobody was allowed to leave the country out of his personal preference.
【正确答案】正确答案：以前曾经出现过这种情况，移民限制极为严格，不许任何人出于个人考虑而迁居他国。
【答案解析】解析：(bottleneck“瓶颈”，引申为“限制”；preference“偏爱”，引申为“考虑”。)