I been having the same problems, already finished four chapters, and in all I have had the same problem, I just hope and this does not affect the grades.

Hi Tamara, 

The lesson questions are “practice-only” questions and they are not graded.  Once you fill-in-the-blanks, the system should prompt you to “check you answer” against the correct answer.  These questions are not supposed to be marked correct or incorrect so it really doesn’t matter if you enter a few words or an entire sentence.  The idea is to see if your answer matches the answer from the course.   If you feel you have answered correctly, please move on through the course.  Only the unit and final exams count toward your grade and these exams are multiple-choice so you won’t experience this issue on the questions that are graded. 

I hope this helps.  Please let me know if you have other questions.

Jan