Complete the following sentence

Complete the following sentence with a (compound) word derived from the one(s) given in bracket.

It suddenly became（ ）for people to share their privacy in WeChat Friend Circle. (fashion)

本题考查常见名词的形容词形式。
由系动词become可知，空缺处应填形容词，fashion是名词意为“时尚”，其形容词形式是fashionable意为“流行的”，需要注意的是，“微信朋友圈”的通常表达是“WeChat Moments”。
句意：人们在微信朋友圈里分享自己的隐私突然成为了一种时尚。