¿en dónde se ubica la cordillera de los andes? a. américa del norte b. américa del sur c. américa central d. norte américa

Okay so i'm taking an online spanish course (penn foster), and in the study guide, you have to create a bunch of sentences with words you've learned so far. translating, reading, and those kinds of things are fairly easy, but when it comes to making my own sentences, my brain just kinda waltz's away. anyone got any tips?

The coexistence of several nationalities within a larger state is known as?

Whats the difference between saber and conocer