is good your health.A. Walk, toB. Walking, toC. To walk , withD. Walking, for

is good your health.
A. Walk, to
B. Walking, to
C. To walk , with
D. Walking, for

A. Walk, toB. Walking, toC. To walk , with(答案→)D. Walking, for解析：不定式与动名词都可以在句中作主语，一般情况下,不定式与动名词作主语可以互换，但不定式常常指某次具体的、将要发生的行为;而动名词则表示一般的、抽象的行为。例如: To save money now is not easy. 现在攒钱不容易。 Saving money is a good habit. 攒钱是个好习惯。“散步有益于健康。”是一般的、抽象的行为。故选D。

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