Prefecturals are over and the Iwatobi Swim Club members are pleased by the progress they have made.  A local summer festival gives them an opportunity to relax.  When Nagisa finds out that Rin is also at the festival, he orders Rei to follow Rin and make sure that Haruka and Rin do not meet.
So we have to make sure they don't meet.
Also müssen wir sichergehen, 
dass sie sich nicht begegnen.
En pocas palabras, no debemos dejar 
que ambos se encuentren, ¿cierto?
Es decir, no podemos dejar 
que los dos se vean, ¿no?
Il faut donc s’assurer 
qu’ils ne se voient pas.
Quindi sarebbe meglio se non si incontrassero.
Então temos que fazer com 
que eles não se encontrem.
Значит, нужно следить,
чтобы они не пересеклись.