quote:
You can think of your turn being comprised of four parts:
Action
Move
Bonus Action
~~~~
Reaction
Everything you do will fall into one of those categories. A bonus action is more like a type of action rather than just another opportunity to perform one of your normal actions and is therefore pretty narrow. There are a lot of class abilities and spells that are bonus actions. So, in a sense, you always have a bonus action, you just don't always have the opportunity to use it. That is the way I think about it anyway.
I separated reaction from the rest because reactions (typically) happen on someone elses turn and are triggered by external circumstances. An attack of opportunity is an example of a reaction. So is the spell "Shield".
You can break your action, move, and bonus action up however you want. Example:
Move: Get up (uses half your movement)
Action: Cast Fire Bolt
Move: Move 15' away from Zombie.
Bonus action: Cast Expeditious retreat.
I am not suggesting you cast that, it is just a spell that has a casting time of a bonus action that you happen to have. Notice that the spell allows you to take the dash action as a bonus action on your turns.
Another example of play from a duel wielder would be:
Move: Move up 10' to orc 1
Action: Attack action (kills orc 1)
Move: Move 15' to a different orc 2
Bonus action: off-hand attack v orc 2
Then on the orc 2's turn, she attacks then moves away, incurring an attack of opportunity (AoO):
Reaction: Use AoO against fleeing orc 2.
Ok, so you move 15' feet away and the zombie advances 40' (using it's move and its action). There is 5' of space between you and it (note that casting a ranged attack spell at close range is done at disadvantage, but that doesn't apply to you).
When you had cast the fire bolt the previous round, you saw the rotting form of what looked to be a farmer, or other peasant. His clothes were somewhat torn and worse for wear, but otherwise ok. The skin on his face looks stretched and gaunt.
Now that he is close, and the light source behind him, all you see is a shambling silhouette, but you smell the stench of putrid flesh.
You release another fire bolt that anyone of even marginal dexterity would be able to dodge, but the zombie seems to almost lean into it, through it doesn't appear too phased by it. It does, however, re-illuminate the situation, leaving his coat smoldering with small orange flames.
(You can still move and take any other legal actions this turn).