pen
The word 'penna' is used in Italian to refer to a pen, a writing instrument that uses ink to produce text or drawings. It is a common item found in offices, schools, and homes. The word can also refer to a feather used for writing, similar to the original use of the English word 'pen'.
I lost my pen
This is a simple sentence in Italian, expressing the loss of a personal item - in this case, a pen. The verb 'ho perso' is a specific conjugation of the verb 'perdere', which stands for 'to lose'. 'La mia' is the definition of personal possession, equivalent to 'my' in English.
Can I borrow your pen?
In this instance, 'posso' is the Italian verb for 'can'. The word 'prendere' stands for 'to take' and 'in prestito' is the Italian way of saying 'borrow'. The word 'la tua' refers to 'your'. This statement is a request to borrow a pen from someone else.
That pen is very expensive
This sentence indicates the high price of a pen. 'Quella' is a demonstrative pronoun meaning 'that'. 'È' represents 'is' in English, and 'molto costosa' translates directly to 'very expensive'.