Usage of cause prepositions at, for and with

1)at: as a cause preposition, you just need to remember a few fixed phrases: surprised-surprised …; Be amused by-be amused by; Very happy-very happy; Wait a minute. You can find that when someone is in a certain mood for some reason, you can use at. Another example: ridicule-I was amused by her jokes because I was amused by her jokes.

2)for: the most commonly used reason preposition, equivalent to because, followed by something. /do sth. For example: being brave-being rewarded for bravery; She laughed too hard to speak. -She laughed speechless. In addition, it should be noted that for, as a conjunction, also means because, because …, usually follows the declarative sentence, indicating the reason in a weak tone, mainly as a supplementary explanation or explanation, not indicating the direct reason. At this point, add a comma before for. For example, she doesn't go out in winter because she feels cold. She doesn't go out in winter because she is afraid of the cold. Fear of cold may not be the direct reason why she doesn't go out.

She was trembling 3)with fear. -She was trembling with fear; The grass was wet with rain. The grass is wet because of the rain.

I hope I can help you.