2 sentences

1. 你怎么这么健忘？

   nǐ zěn​me zhè​me jiàn​wàng?

   How can you be so forgetful?

   Source: OpenSubtitles

2. 他年纪大了，变得越来越健忘。

   tā nián​jì dà le, biàn de yuè​lái​yuè jiàn​wàng.

   As he gets older, he is becoming more and more forgetful.

   Source: Dong Chinese Dictionary