"لا أَعْرِف صَديقهُ بوب."

Translation: I do not know his friend Bob.

[Santiago_G18]

How does "I don't know" work here? I don't understand

[EAni4]

لا not,
أَعْرِف I know.
So together they mean something like "I know not" (which may sound stilted today but was once a common way to say "I don't know" in English).

[Devon.Keogh]

Is Bob the subject of the verb here? Or is Bob the person the speaker is talking to, in which case a better grammatical translation would be "I don't know his friend, Bob? This has been confusing me in these lessons.

[phuvtuo]

"I" is the subject of the verb. Bob equals the friend that you do not know. Bob is the direct object of the English sentence.