Affirmative Subject pronoun be Other words
I 'm 15 years old.
He/She / It ¹___ from London.
We / You / They ²___ Harry's cousin(s).
Affirmative Negative Question Answer
I'm I'm ³___ Am I...? Yes, you
He's He Is he ... ? are. / No, you They're ⁴___ Are they aren't.
They ...? Yes, he is. /
No, he isn't.
Yes, they are./
No, they aren't.
сделать.

1 A friend of mine told me that his dad had given up smoking two years before.
2 A friend of mine said that school and parents would combine their efforts in “war” against smoking the following month.
3 A friend of mine explained me if we united then,we would fight off dangerous habits the following day.
4 A friend of mine told me that they had discussed the health dangers at the Debating Club the previous week.
5 A friend of mine said that he liked to spend his free time there,at the Debating Club.
6 A friend of mine explained me that many people beleived that drugs were fashionable that day.

Берем предложение China imported a record amount of Russian crude last month и преобразуем в следующие видовременные формы:

Present Simple
China imports a record amount of Russian crude monthly.

Present Continuous
China is importing a record amount of Russian crude these days.

Present Perfect
China has imported a record amount of Russian crude this month.

Present Perfect Continuous
China has been importing a record amount of Russian crude for two years.

Past Simple
China imported a record amount of Russian crude last month.

Past Continuous
While U.S. President Barack Obama was seeking to encourage Chinese criticism of Russia on Ukraine, China was importing Russian crude.

Past Perfect
When U.S. President Barack Obama sought to encourage Chinese criticism of Russia on Ukraine, China had already imported a record amount of Russian crude. 

Past Perfect Continuous
When world leaders gathered in The Hague to discuss nuclear security issues, China had been importing Russian crude for two years.