In the late 1970s, scientists detected “holes” in the ozone layer above the South and North Poles.
Did scientists detect “holes” in the ozone layer above the South and North Poles in the late 1970s?When did scientists detect “holes” in the ozone layer above the South and North Poles?Did scientists detect “holes” in the ozone layer above the South and North Poles in the late 1970s or in the late 1980s?In the late 1970s, scientists detected “holes” in the ozone layer above the South and North Poles, didn't they?At midnight, we were still driving through the desert.
Were we still driving through the desert at midnight?When were we still driving through the desert?Were we still driving through the desert at midnight or at midday?At midnight, we were still driving through the desert, weren't we?
