Thanks a lot, guys! Very useful!

Hi Diego, The passive voice in English can be very difficult to pick out, even for English speakers. The first thing to think about is who has the power in the sentence, the action (verb), or the subject or object (I, Bob, her, dog)? In active voice, the subject has the power "Bob gave her a present." 'Bob' (subject) is doing the action and is receiving, so Bob has the power. In passive voice, the power is given to the action (verb) and not the subject or object." The present was given to her by me." The power is given to the action and not the subject or object. One way you can tell it is passive is if you see or hear the verb "to be" and a past participle, WAS (to be, in past tense) GIVEN (past participle). A dead give away of passive voice is if "been" is in the sentence, like "HAS BEEN GIVEN to her." I hope that helps!

I am sometimes frustrated by my inability to understand spoken English.

"Sometimes my inability to understand spoken English is frustrating"