问题补充：
Who did the teacher have how the computer?
A. to show, to use
B. showed, use
C. shown, using
D. show, to use
答案：
A. to show, to use
B. showed, use
C. shown, using
(答案→)D. show, to use
解析：如何使用电脑。how to use the computer 排除 B C。由 did 判断have是实意动词。结合意思是老师让谁展示如何使用电脑。have sb do sth.
