The group trains so that everyone can pair with any other team member and use their powerful Unison attacks. But Shirabe is having trouble pairing up with anybody but Kirika, because of her inability to trust others.
The tears you only notice 
after you've lost them
الدّموع التي لا تلاحظها إلّا بعد أن تفقدها
Die Tränen, die dir erst
nach dem Verlust auffallen,
porque las lágrimas que derramas
tras perder algo son lo más cruel.
porque las lágrimas que derramas
tras perder algo son lo más cruel.
Le lacrime versate quando hai perso qualcuno
Pois as lágrimas que caem
depois que perdemos
О слезах вспоминаешь, когда их лишаешься.