Trees were being planted here this time last year.变过去进行时主动语态快

问题描述:

Trees were being planted here this time last year.变过去进行时主动语态

we/they/people were planting trees here this time last year.
主语没有明确给出,只要是人就行

people were planting trees here this time last year.

They were planting trees here this time last year.