单项选择题
Daylight savings time is a form of zone time that adopts the time（）.
A.one zone to the east B.one zone to the west C.two zones to the east D.two zones to the west
单项选择题 Dacron sails，when not in use，may be damaged if（）.
单项选择题 Cyclones that have warm sectors usually move（）.
单项选择题 Cumulus clouds that have undergone vertical development and have become cumulonimbus in form，indicate（）.
