Use the crew's name.
On a yacht it can help when you preface an instruction with the name of the person to whom it is addressed, they are much more likely to hear the details correctly, because you will have their attention over the noise of the wind in the sails or the engine running.
Other crew members will also be less likely to act prematurely because they think the order is for them. A good example would be when you need mooring lines cast off in a specific order.
"John, cast off" being preferable to "Cast off John".
If you are taking a yachting course with a school, it is vital that you learn everyone's name quickly. Apart from being curteous, you will find commanding the vessel much easier if you can address everyone by their name.
On yachting courses It is common to find that you forget the names of the other students almost as soon as you have been introduced. A experienced instructor will realise the importance of this point and will have several strategies to ensure that they are remembered.
One is to have a written drinks list by the galley with drinks preferences written next to each persons name.
Another is to repeatedly use everyone's name when giving instruction or talking, until it is obvious that it is no longer needed. If the instructor does not remember everyones name-look for a different sailing instructor!
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