What are the differences between the French army and the Mexican army

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?

What is agudas & llanas & esdrújulas & sobresdrújulas

Write 4 sentences using the imperfect tense. use 2 regular verbs and 2 irregular verbs.