As your instructor advised，you ought to spend your time on something ________ researching into．
A.precious
B.worth
C.worthy
D.valuable
网友回答
B解析precious意为“宝贵的，完全的”。worth意为“值得的”。worth后面一般跟动名词，意为“值得做某事”；而worthy表示“值得做某事”时，一般的用法是worthy of doing或worthy to be done。valuable意为“有价值的，值钱的”。比较词义和用法，B项为最佳