The growth of its core social network is slowing down.

其核心社交网络的增长正在放缓。

In May it introduced Facebook Shops, enabling businesses to set up a single online store on its core social network and its sister app, Instagram.

去年5月，Facebook推出了Facebook Shops，让企业可以在其核心社交网络及姊妹应用Instagram上创建一个统一的在线商店。

Adults over the age of 18 are spending 31% less time on Facebook's core social network compared with two years ago, which will translate into fewer opportunities to sell ads.

与两年前相比，18岁以上的成年人花在脸书核心社交网络上的时间减少了31%，即意味着销售广告的机会更少。