French language Q&A Forum

I don't understand when to use these two "en" and "le/la". For example:

La liberté d'expression est un droit fondamental mais il faut ________ respecter les limites.

I know that "en" refers to La liberté d'expression, but why can't we use "la"?

Can you please confirm the pronunciation of LE PLUS when it comes in the middle in case of Superlatives - 

W/ VERBS

- Je travaille le plus dans ma famille. (ploo) ?

W/ NOUNS

- J'ai le plus d'amis. [I have the most friends.] (ploo) OR (plooS)?

- J'ai ramassé le plus de feuilles. (ploo) OR (plooS)?

And if it was Comparitive with Noun, then,

- J'ai ramassé plus de feuilles que toi.  (plooS)?

I found this link below, but this only gives the scenario of Superlatives with Verbs & Adjectives but doesn't give the scenario of Superlatives with Nouns.

https://www.lawlessfrench.com/grammar/plus/

1  nous avions chaussé nos après-skis: I’m guessing this means they were shod in snow boots, but was curious why après-skis is pluralised with an s on the end - nos après-ski was marked wrong. 

2 Les enfants étaient tout excités : I should know, but if the children were girls, would it be tout excitées or does the adjective have to agree with "enfants"? It was a good opportunity to revise the complex rules around "tout" modifying an adjective!

In one quiz, a sentence reads  J'étais comme votre fils, jusqu'à ce qu'un jour, j'aille dans la bibliothèque de mon quartier,et que je me mette à dévorer les romans “Donjons & Dragons”. I filled the blanks correctly because the tips said to use the subjunctive, but I don't understand why the subjunctive is used here. "I was like your son until one day I went to the library ...", something that definitely happened in the past, so I would have written "je suis allé dans la bibliothèque ... et je me suis mis à dévorer ..." I'm also surprised by the second "que" before "je me mette". Can you give me some insight?

Whilst not specific to this lesson - there are lot of references in these lessons to language choices that are "more elegant" than another.  Is this just another way of saying "more formal", or do the French have a specific desire or appreciation for elegant language?  In English we would never describe our language choices as one way being more elegant than another.  I'm just curious!

Est-ce qu'il y a une différence entre "futur" et "avenir"?

J'ai appris "avenir" en tout cas, et "futur" pour dire "le futur simple" par exemple.

Mon frère ________ quand on joue ensemble

why me fait mal is correct but fait mal à moi is incorrect ?

The see examples are written in English, not French, even in the test. It looks like this page needs editing!