【题目】The student is really ________, and he often studies late into the night.
A.openminded
B.hardworking
C.selfconfident
D.warmhearted

【答案】B
【解析】openminded意为“思想开明的”；hardworking意为“勤奋的”；selfconfident意为“自信的”； warmhearted意为“热心的”。结合句意选B。句意：这位学生确实很勤奋，他经常学到深夜。故选B。