4 sentences

1. 他坐在窗边，长叹了一口气。

   tā zuò zài chuāng biān, cháng tàn le yī kǒu qì.

   He sat by the window and gave a long sigh.

   Source: Dong Chinese Dictionary

2. 老王叹了口气，对我说道：“这件事太难办了。”

   lǎo Wáng tàn le kǒu qì, duì wǒ shuō​dao:“ zhè jiàn shì tài nán bàn le.”

   Lao Wang sighed and said to me, "This matter is too difficult to handle."

   Source: Dong Chinese Dictionary

3. 她幽幽地叹了一口气，眼神中充满了哀伤。

   tā yōu​yōu de tàn le yī kǒu qì, yǎn​shén zhōng chōng​mǎn le āi​shāng.

   She gave a faint sigh, her eyes filled with sorrow.

   Source: Dong Chinese Dictionary

4. 他不无感慨地叹道：“这真是奇迹啊！”

   tā bù wú gǎn​kǎi de tàn dào:“ zhè zhēn shì qí​jì a!”

   He sighed with emotion, 'This is truly a miracle!'

   Source: Dong Chinese Dictionary