Without external pressure, it is unlikely the civil rights abuses would have stopped.假如没有外界的压力，践踏民权的情况是不可能停止的。You can't expect these people to go straight when no one's ever going to give them a job.假如没有人给这些人一份工作的话，就别指望他们会改邪归正了。There will be a picnic, if nothing prevents.假如没有什么阻碍的话，将要举行一次野餐。