Learn Italian: Sei pronto? Collegalo subito. - Are you ready? Connect it immediately.

In Italian, when you give an affirmative informal command (telling someone to do something), object pronouns like lo (it) must attach directly to the end of the verb. Since the command form of collegare (to connect) is collega, adding lo makes it collegalo.

Wait, shouldn't the "tu" form of an "-are" verb end in "-i", like "tu colleghi"? Why is it "collega"?

That is exactly how it works for the regular present tense! However, for affirmative commands (the imperative mood), verbs ending in -are use an -a ending for the tu form. So while "you connect" is tu colleghi, the command "connect!" is collega.

Does attaching "lo" change which syllable is stressed when I say "collegalo"?

No, the stress stays exactly where it was on the original verb. The word collega has the stress on the le (col-LE-ga). When you add lo, the stress stays on the le, so you pronounce it col-LE-ga-lo.

What if I wanted to say "Connect them" instead of "Connect it"?

You would just swap the pronoun attached to the end of the verb. If "them" refers to masculine or mixed objects, you use li to make collegali. If it refers to feminine objects, you use le to make collegale.