period of activity meaning in English

活动期

In established cases ( rheumatoid arthritis ) there are periods of activity and periods of quiescene
如确定是类风湿关节炎，其活动期与静止期往往交替出现。
It is an ancient extinct volcano , during whose period of activity ( 3 . 12 . 6 million years ago ) it is thought to have risen to 6 , 500 m
肯尼亚是古代的一座死火山，在它的活动期（约310万260万年前），它的高度可能达到过6500米。
The general appearance should be that of a well proportioned dog , the smooth outline showing quality , gracefulness and perfect balance , combined with sufficient substance to ensure that it is capable of enduring long periods of activity in its intended task as a working sheepdog
作为一只工作牧羊犬,他需要是非常匀称,能够展现高品质流畅轮廓,优雅和完美平衡,结合充分精力,保证它能够承担长时间工作任务。