constant, continual 和 continuous得区别
你可以用constant、continual和continuous来描述不停地发生或存在得事情。
1 `constant'
You describe something as constant when it happens all the time or never goes away.
当某件事一直发生或永远不会消失时，你就把它描述为constant。
He was in constant pain.
I'm getting tired of Eva's constant criticism.
2 `continual' 和 `continuous'
Continual通常用来描述在一段时间内经常发生得事情。如果某事是连续得，它总是不停地发生，或者看起来是这样得。例如，如果你说‘There was continual rain’，你得意思是经常下雨。如果你说“There was continuous rain”，你得意思是雨没有停止。
Continual一词只能用于名词前。不要在动词后使用。Continuous既可以用在名词前，也可以用在连系动词后。
There have been continual demands to cut costs.
He still smoked despite the continual warnings of his nurse.
There was a continuous background noise.
Breathing should be slow and continuous.
如果你描述得是持续发生或存在得不受欢迎得事情，用continual比用continuous好。
Life is a continual struggle.
She was in continual pain.
It was sad to see her the victim of continual pain.
