When your vessel is on or near the path of an approaching tropical storm the（）.

单项选择题When experiencing heavy winds，you should reef sails to（）.

A.bring the sails parallel to the wind
B.reduce sail area exposed to the wind
C.allow the sails to catch more wind
D.remove all tension on the main and jib sheets

单项选择题When a tornado moves over the water from land it is called a（）.

A.Tornado
B.Waterspout
C.Hurricane
D.Cyclone

单项选择题Wen a hurricane passes over colder water or land and loses its tropical characteristics，the storm becomes a（n）（）.

A.High pressure area
B.Extratropical low-pressure system
C.Tropical storm
D.Easterly wave

单项选择题When a hurricane passes into high latitudes over colder water and the source of heat is disrupted，the storm assumes the characteristics of（）.

A.a high pressure area
B.an extratropical cyclone
C.a tropical storm
D.an easterly wave

单项选择题What kind of pressure systems travel in easterly waves（）.

A.High pressure
B.Low pressure
C.Subsurface pressure
D.Terrastatic pressure