threaten ·verb (HAPPEN)
Definition: If something bad threatens to happen, it is likely to happen. Level: C2
冲突威胁要蔓延到邻国。
The conflict ___threatened to spread to neighbouring countries.
然而，当原子弹威胁要将人类从地球上抹去时，这种持续的技术进步变得可疑。
However, this ongoing technological progress became questionable when the atomic bomb ___threatened to wipe humanity off the face of the earth.
经济危机威胁要破坏整个地区的稳定。
The economic crisis ___threatens to destabilise the entire region.