问题
选择题
The experiment show that proper amount of exercise, if ________ regularly, can improve our health.
A．carry out
B．carried out
C．to carry out
D．being carried out
答案
答案：B
考查分词做状语。proper amount of exercise与carry out构成被动关系。Carried out regularly在句中做条件状语。句意：实验显示，如果经常进行，适当数量的锻炼可以改善我们的健康。