A cicada throws its slough.蝉是要蜕皮的.A cicada sloughs off its old skin every spring.蝉每年春天蜕皮.Other insects such as cicada have 3 periods in its lifecycle.而另一些昆虫,像蝉,一生中有3个阶段.The cicada made by green jade is the symbol of luck...
水泥浆的密度和流量是固井施工过程中的两个重要参数.Mud fluid's density and flow are two important parameters during well cementation.砖可以干铺,也可以水泥浆砌合.They can be laid dry or with cement grouting.因此, 决定采用化学发气泡沫水泥浆封固气层.Thus, chemical gas foamed ...