2 sentences

1. 马克思主义首先是一门科学。

   Mǎ​kè​sī​zhǔ​yì shǒu​xiān shì yī mén kē​xué.

   Marxism is first of all a science.

   Source: OpenSubtitles

2. 马克思主义是该政党的指导思想。

   Mǎ​kè​sī​zhǔ​yì shì gāi zhèng​dǎng de zhǐ​dǎo sī​xiǎng.

   Marxism is the guiding ideology of the party.

   Source: Dong Chinese Dictionary