I hear this kind of CD-ROM is very popular.–Let’s buy one before it ____________.

The children are standing_____ to get on the bus.[ ]

Were the audience allowed to join in the play?—Yes, the actors_______to satisfy the audience were successful.

We don’t have enough nurses to look after the patients. At least _____ are needed.

Have you found your English book?—No, I haven’t found ________, but I borrowed ________ from Jack this afternoon.