à and de with the article: au, aux, du, des
CEFR A1 · part 2
edumaterial's parts within the level. The European framework does not subdivide them.
The partitive: du, de la, desUsing du, de la or des before uncountable things, and switching to de after a negative.Adjectives: before or after the nounPlacing the adjective correctly and making it agree, including irregular feminine forms.Passé composé: avoir or être?Choosing the auxiliary, forming the participle and agreeing when required.Son, sa, ses: they agree with the thingChoosing the possessive by the gender and number of the thing owned, not the owner; and…C'est or il estUsing c'est to introduce or identify —with an article after— and il/elle est to describe…The three ways of asking a questionAsking the same question three ways and knowing which each situation calls for…The rule, in three lines
à and de must merge with le and les: au, aux, du, des. With la and l' nothing happens.
The usual slip. Writing à le and de le, because English never merges a preposition with an article.
Why it catches you out. English never merges a preposition and an article — «to the», «of the» — so you write the two words separately and nothing looks wrong to you.