Определить видовременные формы глаголов и их инфинитив

They often discuss their business matters with clients.
Some branches of business will develop fast in the sphere of international cooperation.
We were in Canada last week and we purchased some new equipment there.Now we have brought it to Russia.
The lawyer had given me investment advice before I asked him about it.
Witnesses for the defense are giving their evidence now.

1. discuss - Present Simple (простое настоящее), инфинитив - to discuss2. will develop - Future Simple (простое будущее), инфинитив - to develop3. were - Past Simple (простое прошедшее), инфинитив - to bepurchased - Past Simple (простое прошедшее), инфинитив - to purchasehave brought - Present Perfect (настоящее совершенное), инфинитив - to bring4. had given - Past Perfect (прошедшее совершенное), инфинитив - to giveasked - Past Simple (простое прошедшее), инфинитив - to ask5.  are giving - Present Continuous (простое продолженное), инфинитив - to give