4 sentences

1. 他骗腿上马，动作十分熟练。

   tā piàn tuǐ shàng​mǎ, dòng​zuò shí​fēn shú​liàn.

   He swung his leg over and mounted the horse with great skill.

   Source: Dong Chinese Dictionary

2. 他敏捷地翻身上马，向远方骑去。

   tā mǐn​jié de fān​shēn shàng​mǎ, xiàng yuǎn​fāng qí​qù.

   He nimbly mounted the horse and rode off into the distance.

   Source: Dong Chinese Dictionary

3. 马上上马！

   mǎ​shàng shàng​mǎ!

   Get on the horse immediately!

   Source: Tatoeba

4. 由于资金到位，这个新项目下个月就要上马了。

   yóu​yú zī​jīn dào​wèi, zhè​ge xīn xiàng​mù xià gè yuè jiù yào shàng​mǎ le.

   Since the funds are in place, this new project will be launched next month.

   Source: Dong Chinese Dictionary