Need help with b, c, and d

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?

7. choose the answer that best completes the sentence. (estudiar) para el examen. (2 points) a: estudias b: estudia c: estudiamos d: estudio

Decide whether the sentence is grammatically correct or incorrect as written. ¿te gusta viajas con tu familia? correct incorrect