Revise the following sentences so that their parts are balanced.
a. (Hint: Match verbs.) To improve your listening skills, you should stop talking, your surroundings should be controlled, be listening for main points, and an open mind must be kept.
b. (Hint: Match active voice of verbs.) Paula Day, director of the Okefenokee branch, will now supervise all Eastern Division operations; the Western Division will be supervised by our Oroville branch director, Reggie Kostiz.
c. (Hint: Match verb phrases.) Our newly hired employee has started using her computer and to learn her co-workers names.
d. (Hint: Match adjectives.) Training seminars must be stimulating and a challenge.