Private cars are required to take turns off roads one out of five weekdays ____the

      traffic pressure.?

      A.to reduce               B.reducing?

      C.reduce                          D.reduced?

Private cars are required to take turns off roads one out of five weekdays ___the traffic pressure.

Private cars are required to take turns off roads one out of five weekdays ___the traffic pressure.

A．relieve           B．relieving          C．torelieve          D．relieve

Private cars are required to take turns off roads one out of five weekdays ____the traffic pressure.

Private cars are required to take turns off roads one out of five weekdays ___the traffic pressure.

1. A.
   relieve
2. B.
   relieving
3. C.
   torelieve
4. D.
   relieve