1 Old HSK word(s):

☊钻研 ** B

Definitions from Unihan Copyright © 1991-2015 Unicode® Inc. All rights reserved.

钻 drill, bore / pierce / diamond

研 grind, rub / study, research

Hsk Characters:

HSK -Characters and beyond:

Gb	Big5	Eng	Rad	Mega	Triple	Multilingual

etw. ergründen (V)sich gründlich mit etw. befassen [zuan1 yan2]

钻研