What if ...? Second Conditional

Dear Students,
Last week we worked on the scond conditional. Take a look at these sentences:

If I had a lot of money and time, I would travel around the world.
    past                                          would + verb

If a stranger gave me $1 million, I would travel the world.

Both situations are not real ( I don't have a lot of money or time and no stranger gave me all that money!). So to talk about unreal situations like these ones, we use the following structure:
If  +  subject + verb in the past ..., subject + would + verb
If     Mary   found  my book,   she would  give it to me.

Mothers are the very best invention ever!

Discoveries x Inventions

Last class we talked about discoveries and inventions. Everyone agreed that the internet is one of the very best inventions in all times. We worked on two brief readings about the discovery of DNA and the invention of Google. The discussion will go on next class.

Active and Passive

The last classes were dedicated to the study of the passive voice.
How is the passive voice formed?

                                   Verb To Be + Past participle of the main verb

Present
Active voice: They speak French in Belgium.
Passive voice: French is spoken in Belgium.
                            To be   + past part.

Past
Active voice: Someone broke the window last night.
Passive voice: The window was broken last night.

Present Perfect
Active voice: They have built a new church.
Passive voice: A new church has been built.

Future
Active voice: They will produce ten thousand cars next year.
Passive voice: Ten thousand cars will be produced next year.

Think about the use of the passive voice. When is it normally used? Why?