long periods of

long periods of there were long periods when we had no news of him.period不可数 4.The capacity to be shed for long periods of time.The evolu Being a sailor _____ long periods away from home 英语翻译The periods of validity of operating measurements are no 英语翻译It allows and encourages "over-investment" in periods of Throughout the history of science there have been periods wh 英语翻译the implementation of CASs is effective for periods endi 英语翻译Brave 约翰 has had long periods in __ with serious 感染 and 英语翻译1.I held a series of jobs for short periods,quitting som The（ ）between the two playing periods of a football game is We have about five periods of rapid eye movement sleep durin