This is the formula [by which I solved the math problem ______ ].→方式
I used a sharp knife [with which I opened the can _____ ].→工具
John is the guy [with whom I went to the party _____ ].→同伴
I went to a park [in which I found the stray dog ____ ].→地点
in which →where →I went to a park where I saw the dog.
by which →how →This is the formula how problems can be solved.
——劉美君. (2012). 英文文法有道理! 重新認識英文文法觀念. 聯經.