I haven’t written to him for 3 weeks. = The last time………………………………………………………………
It’s months since we decorated this room
=We haven’t…………………………………………….
I didn’t know how to swim until I was 17 years old.
=Not until

As the boys sleep, military airplanes battle fiercely above the island. none of the boys sees the explosions and flashes in the clouds because the twins sam and eric, who were supposed to watch the signal fire, have fallen asleep. during the battle, a parachutist drifts down from the sky onto the island, dead.