it is time for us to do something to stop pollution同一句 it is {} time that we {} something to stop pollution

it is time for us to do something to stop pollution同一句 it is {} time that we {} something to stop pollution
it is time for us to do something to stop pollution
同一句 it is {} time that we {} something to stop pollution

it is time for us to do something to stop pollution同一句 it is {} time that we {} something to stop pollution
it is high time that we do something to stop pollution.

high 、did ，it's high time that sb. did sth.固定短语

it is time for us to do something to stop pollution
it is {high} time that we {did } something to stop pollution