Stop!
You can't have:
A drip without a drop
A plip without a plop
A rabbit without a hop
Karate without a chop
A fizz without a pop
A flip without a flop
A bottom without a top
A city without a shop
A cleaner without a mop
An exchange without a swap
A surgeon without an op
A skinhead without a crop
A police car without a cop
Or a start without a...STOP!