How do you conjugate the perfect tense in Italian?

To form the perfect tense, you need two parts. The first part is known as the auxillary verb, which is either avere or essere. The second part is known as the past participle. So to say "I bought" in Italian, you say "ho comprato". This guide shows how to form "I bought" in Italian:

1. Take the verb you want to use (e.g. comprare)

2. Remove the -are/-ere/-ire so you are left with the stem (compr)

3. For -are verbs: add -ato. For -ere verbs: add -uto. For -ire verbs: add -ito (comprato)

4. Decide whether the verb needs avere or essere. A simple way to decide is to ask: what did I do? In the case of comprare, we would ask: what did I buy? As this sentence makes sense in English, use avere. (avere comprato)

5. Decide which part of avere we want to use. As we want to say "I bought", we need to take the I form of avere, which is "ho". 

This then leaves us with ho comprato.