Lǎo Zhāng zài qún lǐ fāqǐle yī gè zhōumò páshān de huódòng, shí jǐ gè rén bàomíng le

老张在群里发起了一个周末爬山的活动，十几个人报名了。

Old Zhang initiated a weekend hiking activity in the group, and over a dozen people signed up.