2 sentences

1. 希腊当然只是冰山一角。

   xī​là dāng​rán zhǐ​shì bīng​shān​yī​jiǎo.

   Greece is of course just the tip of the iceberg.

   Source: AI Challenger 2017

2. 书中收集的20个记录详实的案例只是冰山一角。

   shū zhōng shōu​jí de20 ge jì​lù xiáng​shí de àn​lì zhǐ​shì bīng​shān​yī​jiǎo.

   The 20 well-documented cases collected in the book are just the tip of the iceberg.

   Source: CCMatrix