Reader ZBC asks:
"What's the difference between 'doubt' and 'suspect'? In the English-Chinese dictionary, both are explained as '怀疑'."
This is a classic example of how not to study English by relying on English-Chinese dictionaries.
Without consulting an English-Chinese dictionary, I understand it to be accurate that the primary translation for both 'doubt' and 'suspect' can be '怀疑'. However, when you attempt to put '怀疑' back into English, you want to be careful because 'doubt' and 'suspect' each gives quite different connotations.
When you suspect that something is going to happen, you're inclined to believe that it is likely to happen. When you doubt something is going to happen, you believe it is unlikely to happen.
Example. When you say "I doubt he is telling the truth", the message is you think he's lying. He may well be telling the truth, but you don't trust him. You don't believe his words.
However, when you say "I suspect he's telling the truth", you believe his words.
In the comedy Four Weddings and a Funeral starring Hugh Grant, the priest was presiding over the wedding of Charles (played by Grant), saying:
"Dearly beloved, we are gathered together here in the sight of God and in the face of this congregation to join together this man and this woman in holy matrimony, which is an honorable estate, instituted of God in the time of man's innocence, signifying unto us the mystical union that is betwixt Christ and his Church and therefore is not by any to be enterprised nor taken in hand unadvisedly, lightly, or wantonly, but reverently, discreetly, advisedly, soberly, and in the fear of God.
"Therefore, if any man can show any just cause why they may not lawfully be joined together, let him speak now or else thereafter for ever hold his peace."
Then when Charles' mute brother raised noises, the priest asked Charles what his brother was trying to say.
Charles: "He wants me to translate what he's saying."
Priest: "What is he saying?"
Charles: "I think the groom is having doubts... He says 'I suspect the groom is having doubts. I suspect the groom would like to delay. I think the groom really loves someone else.'"
Priest: "What's he saying?!"
Charles: He says he suspects the groom loves someone else.
Priest: "Do you? Do you love someone else? Do you, Charles?
Charles: "I do."