The manager_____ the workers how to improve the program since 9 a.m.
| A．has told | B．is telling | C．has been telling | D．will have told |
It doesn't matter ________ you pay by cash or credit card in this store.(2012·山东 )
| A．how | B．whether | C．what | D．why |
Believe it or not，I'm sure that is ________ people call the six sense.
| A．when | B．what | C．which | D．why |
________ several times，but he still doesn't know how to do it correctly.
| A．Although I've taught him |
| B．I've taught him |
| C．Having been taught |
| D．Having taught |
Information technology is taught in most schools，________ we have entered the information era.
| A．so | B．while |
| C．for | D．still |
It's really very dangerous.One more step，________ the baby will fall into the well.
| A．or | B．so | C．but | D．and |