нужна помощь, необходимо написать в прошедшем и будущем времени . Заранее спасибо.

1Students will have an obligation not to be late for their lessons.Students were obliged not to be late for their lessons.2The camel will be able to carry heavy lads across great deserts.The camel could (was able to) carry heavy lads across great deserts.3He will be allowed to sleep in this room.He was allowed to sleep in this room.