How to say happy birthday to my grandpa in spanish?

Can you me with this spanish worksheet

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?

Escribe el movimiento artístico que completa la frase. write the artistic movement that completes the sentence. el es un movimiento que se caracterizó por representar la realidad de una manera absurda y fantástica.