que: It is important that you understand. >> (I think I have this one right but I want to double check, "Es importante que intiendo". It is in the subjunctive tense.) He was going to drive alone.|||Hello, you do need to use the present subjunctive form in this case: Es importante que entiendas. (informal) For formal: Es importante que Ud. entienda. For plural- you when talking to a group of people Es importante que Uds. entiendan. I overlooked the second part, so here it is now: He was going to drive alone. Iba a conducir solo. Subjuctive not necessary here. :) Uses imperfect tense.