How many actions in combat does PC have while opponents under sleep spell?

Question

Scenario: one PC vs a group of opponents

PC wins initiative and goes first. He casts sleep and all opponents go to sleep (assuming all conditions of sleep spell are met). Sleep says it lasts one minute and targets will only wake up if they take damage or are slapped/shaken awake.

Based on the step by step combat box on PHB 189, step 5 says "Begin the next round. When everyone involved in the combat has had a turn, the round ends. Repeat step 4 until the fighting stops."

PC hits first and all opponents are sleeping, they can't take a turn so when would that round end?

Q1a: If answer is, "They awake after a minute.", would the following be true?

Each round being 6 seconds (PHB 181 & 189) would mean PC has 10 rounds or 10 'Actions In Combat' he can use (PHB 192-3) before they wake up. As long as opponents don’t take damage or awake by slap/shake. Is that correct?

Answer 1

You are correct, the PC has 10 turns

Firstly, sleep makes creatures fall unconscious:

Starting with the creature that has the lowest current hit points, each creature affected by this spell falls unconscious until the spell ends, the sleeper takes damage, or someone uses an action to shake or slap the sleeper awake.

"Unconscious" is a status condition defined in PHB 292. When you are unconscious, you suffer a few effects. The first of those effects states that you are:

• Incapacitated and can't move or speak, and are unaware of your surroundings

"Incapacitated" is another status condition defined in PHB 290. When you have this condition, you:

• Can't take actions or reactions

So in combat, after the PC has won initiative and cast sleep before anybody could act, after they conclude their turn and it becomes the turns of the sleeping opponents, they cannot take actions or reactions, and they cannot move or speak and are unaware of their surroundings. However, they will still take their turns in combat: they just cannot do anything at all during their turn. Essentially, they have to "pass" and forfeit all the things they could have done.

Since the targets are all asleep for 1 minute, the PC then has 10 full turns -- action, bonus action, reaction, movement, free object interaction, free actions (like dropping things), the whole deal -- to do with as they please.