书上例句:My father has had a hard life and it's time he eased off a bit.问题:后面的从句中he eased off a bit .为什么用过去式,而不是现在时.

问题描述:

书上例句:My father has had a hard life and it's time he eased off a bit.
问题:后面的从句中he eased off a bit .为什么用过去式,而不是现在时.