The French preposition à is generally summarized as "to, at, or in," but it has quite a few more meanings and uses than that.
As if the myriad possible translations of à and de aren't enough, these two French prepositions also have complementary and contrasting uses.
One of the eight parts of speech, adjectives are a type of modifier. They serve the same purpose in French and English, but they are very different in two respects.
By definition, adjectives modify nouns. But more than 30 French adjectives can sometimes modify verbs instead, thus taking on the role and characteristics of adverbs, including the fact that they are invariable.
There are six French adjective / pronoun pairs, where an adjective + noun can be replaced by a corresponding pronoun.
When describing someone as capable of doing or determined to do something, a preposition is required between the adjective and verb. In French, the choice of preposition depends on the adjective that precedes it, not the verb that follows.
As you might guess from their name, adverbial pronouns are caught between two worlds: they are pronouns in the sense that they replace nouns, and at the same time they are adverbs representing a place, a quantity, or the object of a proposition. French has two adverbial pronouns: en and y.
French adverbs are descriptors: they can modify several different parts of speech, including themselves. Virtually every French word that ends in -ment is an adverb, equivalent to -ly in English.
Adverbs of frequency express how often the action of a verb occurs.
Adverbs of manner express how the action of a verb occurs. In English, the vast majority of adverbs of manner end in -ly, whereas in French, they mostly end in -ment. They are created from adjectives.
Adverbs of place express where the action of a verb occurs.
Adverbs of quantity express how much, how many, or to what extent.
Adverbs of time express when the action of a verb occurs.