Форум ЗнаниО

Одна деталь вызывает недоумение. Что нужно вставить в предложениях  The foxes are on the         shelf      The buses are on the       shelf   first second fourth third

Предложения.

The foxes are on the fourth shelf.

The buses are on the first shelf.

The shelves are arranged from first to fourth.

The foxes are on the third shelf.