It means "But French is very difficult"
Difficile
'mais quelle est cette ...' means but what is this (thing) / who is this (person).
la langue française est difficile orle français, c'est difficile! orle français est difficile
Il est difficile or elle est difficile, depending on the gender of the noun you are talking about.
''Is absent but hates him''
"Mais ce n'est pas le joyeux ..." means "but is is not the merry ..."
Mais cette amitié est à jamais. -- But this friendship is forever.
Pourquoi l'amour est si difficile? - Why is love so difficult?
It means "not at all." Example: Est-ce que le français est difficile? (Is French difficult?) Pas du tout! (Not all!)
This isn't a complete sentence, but what you wrote translates to "...'who' but it's okay".
Jacques Boulenger has written: 'Valeur critique des textes de Gargantua' 'De la walse au tango' -- subject(s): Dance, History 'Marceline Desbordes-Valmore, sa vie et son secret' 'L 'affaire Shakespeare' -- subject(s): Authorship, Derby theory 'Mais l'art difficile!' -- subject(s): French literature, History and criticism 'The seventeenth century' -- subject(s): History 'Mais l'art est difficile!' -- subject(s): French literature, History and criticism 'Candidature au Stendhal Club' 'Les soirs de l'Archipel' 'The seventeenth century in France' -- subject(s): History 'Marceline Desbordes-Valmore' 'Mais l'art est difficile!' -- subject(s): French literature 'Histoires vraies'
"la vie est dure mais j'aime vivre" means "Life is hard, but I love to live"