The conjunction “but” in “Their English may have been rocky...

Próximas questões
Com base no mesmo assunto
Q2574133 Inglês
Answer question according to TEXT 1 below.

TEXT 1
TRUE STORIES – The School teacher

1 IT'S HAPPENED TO me half a dozen times, lately. I'm walking home through the Edinburgh Gardens and I see them heading towards me. Heavy kids, eight of them, maybe ten. I keep walking, but I keep my eyes on them, and my feet wait for the sign to take off.
2 They are Greeks and Italians, all adolescents, all wearing green or maroon cardigans with a double black stripe round the chest, Levis or Wranglers that fit just right, showing a bit of sock and reddish shoes with big heels. I move across to the outside of the footpath to let them pass. They spread out a little. They're close enough now in the almost-dark for me to see their faces.
3 And it's all right, because the front one is Chris, from Fitzroy High, and he says, 'Hello, miss!' and the others are kids who have grinned and nodded at me a hundred times in the yard at school.
4 I had taught migrants before, but Fitzroy High is one of those legendary inner-suburban schools which can no longer be properly described as Australian. In none of the classes I took were there more than four kids with Australian names. A blond head was a surprise. The administration battled to assimilate these kids into recognizable moulds. In a hundred subtle ways they were defeated.
5 Most of the girls had pierced ears and had worn gold earrings since they were babies. The line was that plain gold sleepers were the only ear decorations allowed. At the time when it was fashionable, in Australia, to wear a zillion colored plastic bangles up your arm, teachers strove hopelessly to prevent this display of gaiety at school. The girls went on wearing them and pulled their sleeves down when they saw a senior mistress coming. 
6 There were weekly segregated assemblies. I don't know what they told the boys, but at one girls' assembly I actually heard the senior mistress say, 'As girls we must be modest, quiet, hardworking and well-groomed at all times'.
7 What astonished me was the stubbornness of the kids' resistance to the rules. They didn't organize or protest. They defied. If the pressure got too much for them, they stayed away. And yet they hated to be suspended. One boy was suspended for a week, and every day I'd see him leaning against my front fence, staring wistfully at the school where his mates were tight-roping their way dangerously through the day.
8 In the three other schools I'd taught at, I'd been an authoritarian, a good disciplinarian. It wasn't only political or educational thinking that changed my attitude at Fitzroy High. It was the kids themselves. I suppose I fell in love with the whole nine hundred of them. In other schools, I'd known kids who were 'trouble-makers' or 'over-achievers', or ‘irresponsible' or 'antisocial. But somehow the kids at Fitzroy cut right through those categories.
9 To begin with, they made me laugh. I can't remember ever knowing such exuberant, merry kids. Every class had more than its share of natural clowns. The plays they invented were full of hilarious delight. In a second-form class I had for a year, two Italian boys called Claudio and Joseph used to present weekly plays so excruciatingly funny that we lay across the desks aching and wiping our eyes.
10 A kid called Ilya wrote wonderful, magical stories; he could write fairy tales his grandparents had told him in Yugoslavia. Lemonia could break your heart with a story about a lost fountain pen, and Dora with an account of her dreams. Their English may have been rocky, but there was a pure, delicate humour lying bone-deep in them that nothing could corrupt.

GARNER, Helen. True Stories. Melbourne, Australia: The Publishing Company, 2013, pp. 26-28. Adapted.
The conjunction “but” in “Their English may have been rocky, but there was a pure, delicate humour lying bone-deep in them that nothing could corrupt” establishes a contrast between:
Alternativas