A．Two nights.B．Two days.C．Four nights.D．Four days.

Pigeons can carry messages for about ______.A．two weeksB．four weeksC．two yearsD．four years

A．One weekend.B．Five days.C．Ten days.D．Two weeks.

How long is the project expected to take？A．Four nights.B．Four weeks.C．Ten days.D．Two weeks

How often does a person dream each night？A．Two to four times.B．Four to six times.C．Every 6

A．One.B．Two.C．Three.D．Four.

A．One.B．Two.C．Three.D．Four.