In all the quizzes in this topic you can use the TAB key to move from box to box. In addition, the TAB key will also move the focus to the Check Answer/Next Question button allowing you to press the enter key once to check your answer and then again to move on to the next question. Use SHIFT TAB to step backwards through the text entry boxes.
Remember that sentences end with a full stop. If the quiz requires you to complete the last word in a definition, you also need to include the full stop at the end of the sentence.