1.The reporter noted there was a serious lack of resources available to us then
2.They admitted the earth was over populated then.
3.Anna said to ride a bike was good for the environment and great for our health.
4.Scientist warn oil spills damage the prime source of water for various cities marine life and even affect birds /Обратите внимание, здесь главное предложение в настоящем.
5.Our teacher explained to us that many chemicals destroyed the ozone layer because they interacted with ozone.
6.A famous ecologist said the use of nuclear energy had led to the threat.
7.The author of the article stated the high amounts of air pollution were caused by the development of several industries and water pollution.
9.I asked myself what the ingredients of these cleaning products were.
Объяснение:
Базовая разница между Past Simple и Past Perfect очевидна. Действие, выраженное Past Simple, произошло в а выраженное Past Perfect – до момента в
Давайте сравним.
Alan finished his essay at 10pm yesterday. – Алан закончил сочинение вчера в 10 вечера. (Past Simple)Alan had finished his essay by 10pm yesterday. – Вчера к 10 вечера Алан закончил писать сочинение. (Past Perfect).В первом случае, at 10pm yesterday дает нам момент во втором случае, фраза by 10pm yesterday указывает на то, что действие произошло до момента.
Единственное, на что Вы должны обратить внимание, это повествовательные предложения, в которых описывается последовательность действий. В подобных предложениях нужно использовать исключительно Past Simple.
Пример:
On his birthday, Jaсk got up at eight. Нe opened his presents and then he went to the zoo with his family. – В свой День Рождения Джек встал в восемь. Он открыл свои подарки, а затем пошел в зоопарк с членами своей семьи
