worsen

1. V-T/V-I If a bad situation worsens or if something worsens it, it becomes more difficult, unpleasant, or unacceptable. 使變得更糟; 變得更糟

The security forces had to intervene to prevent the situation worsening. 那些安全部隊不得不乾預以阻止形勢變得更糟。