1. We received this letter from Continental Equipment a week ago.
2. When we receive your confirmation, we will open the letter of credit.
3. I want to test this equipment.
received - Past Simple Active (простое прошедшее, активный залог), инфинитив - to recieve;
receive - Present Simple Active (простое настоящее, активный залог), инфинитив - to recieve;
will open - Future Simple Active (простое будущее, активный залог), инфинитив - to open;
to test - Simple Infinitive Active (простой инфинитив в активном залоге).