The second form of the conditional perfect is the literary equivalent of the conditional perfect.
The normal word order in French and English is subject + verb, as in vous êtes - you are. Both languages also have what is known as inversion, where the verb and subject pronoun switch places, resulting in êtes-vous - are you. In English, inversion is used only to ask questions, but in French it has several different purposes.
Inversion with the first person singular je is a little trickier than with other subject pronouns. It's also very formal and therefore rare, so one of those grammar concepts you need to recognize but not necessarily use.
Inversion is not limited to pronouns - it can also be done with nouns and proper names, though this is a bit more complicated.
Don't worry, it's not a swear word. In French, explétif is a grammatical term that serves only to draw attention to what precedes it.
In formal, usually written French, there are certain verbs and constructions that can be made negative with just ne - the inclusion of pas or some other negative word is not required.
The object pronoun le can be used impersonally to replace intangibles like adjectives, verbs, and clauses.
Some liaisons in front of a vowel or h muet are optional, which means it up to you to decide whether to pronounce them. However, that decision matters: more liaisons means more formal speech, so obviously fewer liaisons means more informal, possibly even familiar speech.
The passé simple is a single-word past tense, equivalent to English's simple past. However, the passé simple is a literary tense and is thus limited to formal writing, such as literature, journalism, and historical accounts.
The past anterior is the literary equivalent of the past perfect and is usually preceded by a conjunction such as après que or quand.