threat
1.threat是类名词，如We disregarded all his threats里的threats不可改作threat。
2.threat后面可以接不定式。例如：The tenants disregarded their landlord's threat to expel them.
3.注意下面第一句里用of，第二句里用to：
- There was then a continual threat of war.
- There was then a continual threat to peace.
