问题
选择题
The experiment shows that proper amounts of exercise, if _______ regularly, can improve our health.
A．being carried out
B．carried out
C．carrying out
D．to carry out
答案
答案：B
题目分析：句意：这项实验表明适量的运动，如果有规律的完成，可以改善你的健康。这里是省略了相同的主语及be动词，整句完整的话应该是：The experiment shows that proper amounts of exercise, if the proper amouts of exercise is carried out regularly, can improve our health.选B。