青蛙的生命周期包括卵、蝌蚪和成蛙三个阶段。

A frog's ___life cycle consists of egg, tadpole, and adult stages.

这款智能手机的设计考虑了其整个生命周期中的可持续性。

The design of this smartphone takes sustainability into account during its ___life cycle.

了解产品的生命周期有助于企业制定更有效的营销策略。

Understanding the ___life cycle of a product helps businesses develop more effective marketing strategies.