明(あか)る()い() akarui内(うち) uchiに niテント tentoを o張(は)っ()て() hatteしまおう shimaou。 Let's pitch the tent while it's still light out. outdoorsinvitation~内に (while still)volitional form (~う/~よう)~てしまう (regret/completion)テントを張る (pitch a tent)