doubt : 指对事物的真、假有怀疑。 
There is no room for doubt.(没有怀疑的余地。) 

suspicion : 语气较强，指对某人做某事的目的、意图有怀疑，或认为某人做错事，但无确凿证据而产生怀疑 
Since they discovered the truth about his background, his colleagues have regarded him with suspicion.(他的同事虽然摸清了他的背景, 但对他还是疑神疑鬼的。) 

distrust : 一般用词，泛指对某人某事不信任而感到怀疑。 
He looked at the stranger with distrust.(他怀疑地打量着那个陌生人。)

I doubt that she is the criminal.
我不相信她是罪犯。(认为不见得)

I suspect that she is the criminal.
我怀疑她是罪犯。(认为有可能)

Do you doubt what I say?	  
你怀疑我说的话吗?

I doubt whether he will marry her.	  
我怀疑他是否会跟她结婚。

I doubt whether it is true.	  
我怀疑这是不是真的。

He doubted whether they would be able to help.	  
他拿不准他们是否能帮忙。

I doubt if he is honest.	  
我怀疑他是否诚实。

She doubted if he could make a success of it.	  
她怀疑他是否能把这件事干得很好。