问题
选择题
I go to school by _______, but my best friend goes there ______foot.
A．a bike; by
B．bikes; on
C．bike; on
D．bike; by
答案
C
题目分析：句意：我骑自行车去上学，但是我的最好的朋友步行去上学。这里是固定短语by+表示交通工具的名词（用单数）；所以应该是by bike；on foot步行。故选C。