Many Americans have been leaving their cars at home.

问题描述:

Many Americans have been leaving their cars at home.
leave为什么要加ing?

这是一个现在完成进行式表示习惯或情绪的用法的一个句子.
have been doing 是现在完成进行式的构成形式.
译为:许多美国人总是把车留在家里.