It's the athletic festival. Kakeru hurt his ankle during the pole-toppling game, and hid that fact from everyone else. Kakeru tries to keep his suffering to himself, when Suwa and the gang call out to him. Met with everybody's kindness, Kakeru begins to tell them what he's been keeping pent up inside. And then, the class relay begins.
But when you're actually having 
a good time, it's okay to smile.
.ولكن، لا بأس بأن تبتسم إن كنت تحظى بوقتٍ ممتعٍ حقًّا
Aber trotzdem …
pero cuando te diviertas
de verdad, puedes reírte.
pero cuando te diviertas
de verdad, puedes reír.
mais, quand tu t’amuses vraiment, 
rigole de bon cœur.
Ma quando ti stai davvero divertendo, ridi pure.
Mas quando estiver se divertindo de 
verdade, não há razão para segurar o riso.
Но если тебе действительно
весело, почему бы и нет.