In general，the most effective period for observing stars and planets occurs during the darker limit of（）.
When a magnetic compass is not in use for a prolonged period of time it should（）.
In some parts of the world there is often a slight fall in tide during the middle of the high water period. The effect is to create a longer period of stand at higher water. This special feature is called a(n)（）.
All engines in lifeboats and rescue boats shall be run for a total period of not less than（）in weekly inspections.
A cast steel strong back is fitted in way of the combustion space to help absorb （）.
Operating a propulsion diesel engine at less than 30% of designed normal load for prolonged periods will result in （）.
A diesel engine burns （） a gasoline engine of the same capacity in the same period of time.
Jitter is an unwanted variation of one or more characteristics of a periodic signal in electronics and telecommunications and（）refers to call issues that cause variations in timing or time of arrival.
From the period 1795-1916, Poland was divided between in a series of three partitions.
In Elizabethan Period, wrote more than fifty excellent essays, which made him one of the best essayists in English literature.
In the early period of Middle English, English,（ ）existed side by side.
Romantic writers take it as a strong belief in the importance of nature.
The most prosperous period of the silk road established in Sang Dynasty after Tang Dynasty.
What happened in the world history during the period of 1929-1933?
In the early period of Middle English, English,（ ）existed side by side.
English writers in the Victorian period were all concerned about the fate of .
In the English literature of the 17th century, the _______ period is traditionally called 'Age of Dryden'.
If a mark is not actively used for a period of time,normally 10 years in most jurisdictions.
In Germany, the dominant managerial values include a strong sense of profession and pride in work.
Yeat's poetic style changed from sweet romanticism in his early period to the mystic, the philosophical and religious in his mature poetry. _____ is representative of the latter period.
Operations which left patients ______ and in need of long period of recovery time now leave them feeling relaxed and comfortable.
44 . The fact _______ he does so in so short period of time challenges explanation.
The Age of Realism in the literary history of the America refers to the period from _______.
The population of America grew dramatically in the period between 1942--1957 known as
