Translation:Doctor Wang is very busy in the morning.
I think "Doctor Wang is very busy in the mornings" would also work.
There should be logic to catch the "Doctor/Dr." issue as well as time ambiguity in this sentence. "... is very busy in the morning," "....was very busy this morning," "...will be very busy in the morning," are all plausible interpretations of the sentence depending on the context and when this statement was made.