1. Currently they a
re expanding (Present Continuous Active) their business in Europe. Are they expanding their business in Europe currently? Currently they aren't expanding their business in Europe.2. The delegation of Finnish builders
has arrived (Present Perfect Active) in the city today. Has the delegation of Finnish builders arrived in the city today? The delegation of Finnish builders hasn't arrived in the city today.3. We
have assumed (Present Percet Active) that nobody
will buy (Future Simple Avtive) any chocolate when the price
is (Present Simple Active) more than $2 per bar. Will nobody buy any chocolate when the price is more than $2 per bar?4. What contract
were they
discussing (Past Continuous Active) at 11 a.m. yesterday. They were discussing a new contract at 11 a.m. yesterday. They weren't discussing a new contract at 11 a.m. yeasterday.