Q3: Because of wireless service costs plummeting in the last year, and as mobile phones are increasingly common, many people now using their mobile phones to make calls across a wide region at night and on weekends, when numerous wireless companies provide unlimited airtime for a relatively small monthly fee.
- Because of wireless service costs plummeting in the last year, and as mobile phones are increasingly common, many people
- As the cost of wireless service plummeted in the last year and as mobile phones became increasingly common, many people
- In the last year, with the cost of wireless service plummeting, and mobile phones have become increasingly common, there are many people
- With the cost of wireless service plummeting in the last year and mobile phones becoming increasingly common, many people are
- While the cost of wireless service has plummeted in the last year and mobile phones are increasingly common, many people are
d和e区别在哪里,为什么d是正确的..e错在哪里/ | 
