Verbs are words involving doing or being, easy to recognise in English because you can put 'to' in front of them - 'to live', 'to be', 'to speak', 'to pay', 'to have', etc.
In a dictionary, Italian verbs end in -are, -ere or -ire; this form is called the infinitive.
In English we put words like 'you', 'we' or 'they' in front of a verb to show who's doing something. In Italian, this is done by the different endings of the verbs. The words for 'I', 'you', 'we', etc. are usually used only for emphasis.
With some verbs, when the endings -are, -ere or -ire are removed, you are left with a stem to which the endings that indicate 'I', 'you', 'we', etc. can be added.
These are the endings for verbs in -are and -ere. There are some similarities:
to prefer
I prefer
you prefer
you prefer
we prefer
you prefer
they prefer
The way -sc- is pronounced depends on the following vowel, eg as 'sk' in preferisco but as 'sh' in preferisce.
Other common verbs change the stem as well as the endings. They are known as irregular verbs and include essere, 'to be', avere, to have, fare, 'to do', and volere, 'to want'.