I think what this example shows is that the happy activity need not be recreational;

我想这个例子说明快乐活动不必是一项娱乐活动；

youdao

The investigation and analysis of urban public space of medium measure and its activity need hold rational attitude.

中观层面城市公共空间及其使用的调研与分析需要秉持科学理性的态度。

youdao

So, how to determine precursory clustering earthquake and how to fully utilize it to forecast earthquake and to monitor earthquake activity need to be deep studied and probed.

所以，如何判定前兆震群和充分利用前兆震群预报地震和监视未来地震活动有待更深入的研究和探讨。

youdao

So, how to determine precursory clustering earthquake and how to fully utilize it to forecast earthquake and to monitor earthquake activity need to be deep studied and probed.

所以，如何判定前兆震群和充分利用前兆震群预报地震和监视未来地震活动有待更深入的研究和探讨。

youdao