2 sentences

1. 我的自行车胎没气了，需要打气。

   wǒ de zì​xíng​chē tāi méi qì le, xū​yào dǎ​qì.

   My bike tire is flat and needs to be pumped up.

   Source: Dong Chinese Dictionary

2. 比赛前，教练一直在给球员们加油打气。

   bǐ​sài qián, jiào​liàn yī​zhí zài gěi qiú​yuán men jiā​yóu dǎ​qì.

   Before the game, the coach kept cheering the players up.

   Source: Dong Chinese Dictionary