Name one thing that actors had to do differently on the set after the invention of sound.

After the invention of sound, the actors had to use their voice to convey the meaning which they could only do through facial and bodily expressions before the sound was invented.

Explanation:

The invention of sound marked the beginning of a new era in the film industry. Conveying the meaning of the scene became easier as the actors could now say dialogues built of conversations between two or more people sharing the screen. The facility of adding sound also enabled the makers of films to add special sound effects to leave a psychological impact on the minds of the viewers and to make the work more impressive and engaging.

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