2 sentences

1. 他正在帮爷爷铡草。

   tā zhèng​zài bāng yé​ye zhá cǎo.

   He is helping his grandfather cut fodder with a fodder cutter.

   Source: Dong Chinese Dictionary

2. 这口铡已经生锈了，切不动那些坚硬的秸秆。

   zhè kǒu zhá yǐ​jīng shēng​xiù le, qiē bù dòng nà​xiē jiān​yìng de jiē​gǎn.

   This straw cutter has rusted and can no longer cut through those tough stalks.

   Source: Dong Chinese Dictionary