也就是说，人们不需要付钱去使用这些服务，而服务供应商通过广告来牟利。

That is, people pay nothing to use them and the services make money via advertising.

youdao

也就是说，人们不需要付钱去使用这些服务，而服务供应商通过广告来牟利。

That is, people pay nothing to use them and the services make money via advertising.

youdao