They received orders to start at once.
He is under orders to leave for Moscow next Monday.
He ordered his son to buy a newspaper for him.
这种表达方式是错误的
He orders that the work (should) be started at once.
He ordered them to start the work at once.
We have sent an order for a hundred copies of the book.
我们下订单订了一百份这本书。
Your order for a hundred copies of the book has been executed/filled already.
My mother has ordered me a new suit.
Everything is in order.
一切正常有序。
The typewriter is in order.
这台打字机工作正常。
A fresh discussion of the question is now in order.
现在正适合重新讨论这问题。