Can I answer your second question first? Adjective: big, small, fat, bad, funny. E.g. The girl is big. That small girl. I like the girl because she is bad. What a funny girl. These describing words do not need a preposition for the sentence to make sense and be grammatically correct. Preposition + adjective: kind to, friendly to, angry about, bored with, sorry for, interested in. E.g. I am kind to the girl. I am friendly to the girl. I am angry about the election. I am bored with the election. I am sorry for the failure. I am interested in TV. These describing words need the preposition to make sense. E.g. I am kind the girl. This does not make sense because being kind has a direction from one person/thing towards another person/thing. This can be confusing because the adjective can work on its own without the other person/thing. E.g. I am kind. I am friendly. I am angry. I am bored. I am sorry. I am interested. To answer your first question, I give you an example: The rice cooker is faulty, so I burned my rice. The rice cooker is at fault. This is the same as: The rice cooker is broken, so I burned my rice. The rice cooker is to blame. OR The rice cooker doesn't work, it burned my rice. I blame the rice cooker. OR I blame the rice cooker for burning my rice. It burned my rice because it was broken. OR I fault the rice cooker for burning my rice. The fault in the rice cooker caused it to burn my rice. The rice cooker was faulty so it burned my rice. Good luck :)

Hi there. When something is faulty, it is not operating properly, e.g. "I bought and IPhone and I could not hear anyone, I think the speaker is faulty". When you are "at fault"- it simply means that it is your fault or you are to blame e.g. "When I knocked my neighbours postbox over with my car, I was at fault" Hope this helps!

If something is faulty then it is operating incorrectly, e.g "The toaster was faulty and it burnt my bread this morning." If something is at fault then it is guilty of blame for something, e.g. "When I was involved in a car accident last month, the other driver was at fault." In terms of adjectives with prepositions, there is no real way to guess the meaning as with many phrasal verbs. They should be learned by experience and with regular use.