2 sentences for 历时 (lì​shí — last)

1. 整个修建过程历时三年之久。

   zhěng gè xiū​jiàn guò​chéng lì​shí sān nián zhī jiǔ.

   The entire construction process lasted for three years.

   Source: Dong Chinese Dictionary

2. 这项研究前后历时十年才最终完成。

   zhè xiàng yán​jiū qián​hòu lì​shí shí nián cái zuì​zhōng wán​chéng.

   This research took a total of ten years to complete.

   Source: Dong Chinese Dictionary