1. The phone cannot be reached.
2、The call cannot be connected.
3、The line is busy or engaged.
4、The number you dialed is not in service.
5、The recipient’s phone is off or out of range.
6、The call is not being forwarded.
7、The call cannot be completed as dialed.
根据不同的情境，可以选择合适的表达方式。
