Pretty please?

No.

Perhaps I'd better start at the beginning. When young, speakers of many languages are taught to use please and thank you in order to be polite. It therefore comes as a surprise to many people taught to use please and thank you when they find out that things are not always that simple in other languages and cultures. Let me give you some examples to set the scene before we move on to Gaelic.

In Icelandic, there is a phrase for thank you: takk fyrir. Some people find it perplexing that the most common response to takk fyrir is takk takk. That's like saying thank you and someone responding thanks thanks. Amusingly, this is also what happens in Chichewa (a language from Malawi) where you say zikomo for "thank you" and people respond by saying zikomo back at you.

Half way round the globe, learners of Cantonese are faced with the headache of two words for "thank you". One, 唔該 (mgōi), is the more generic one user when asking for something, accepting a service, praise or help, when borrowing something and, funnily enough, in a way that English uses "excuse me" when you're about to ask for something. The other, 多謝 (dōje), is mainly restricted to thanking someone for a gift or compliment. It's also confusing for many foreigners that even though Cantonese society treasures politeness, especially towards older people, phrases that might translate as "please" are rare. For example, if I was asking my grandmother for permission to stay out a bit longer to play, I would not use "please". I might use a particle at the end of my question to make it sound "little" and most certainly I would address her with the proper vocative particle and her "rank" (rank sounds weirder than it is but it's somewhat like calling someone Sir or Madam, in English), but I'd not use "please", as such.

That neatly brings us to Gaelic. While there are several words for saying "thank you" (depending on politeness and someone's dialect), there is no word for "please". Yes yes yes, I know, you've watched Speaking our Language or done some online course where the phrase mas e do thoil e or the politer mas e ur toil e appear for "thank you". Honestly, that's just English-inspired nonsense. These two phrases makes most native speakers want to hide under a blanket or consider violence. At best, those phrases grate on their ears, and they mark you as a learner.

Traditionally, the phrase mas e ur toil e does exist but it is used for a different purpose. Think of costume drama and some servant girl saying "Might I have the afternoon off next Saturday, if it pleases Sir?". That's the kind of situation where you might hear (or rather, have heard) mas e ur toil e. But not in a shop in Ness or the ferry to Mull in 2015.

Yes, some native speakers have indeed adopted this and are using it pretty much the same way as English uses please but on the whole, this is rare and not uncontroversial. Since there are other, more widely accepted ways of being linguistically polite, as a learner I would strongly suggest you avoid it. You'll rarely get brownie points for using it and the chances of a heated argument are high.

So what, I have to be rude?

No. Gaels are rather polite on the whole. They just don't have a word for "please". Instead, there are other ways of showing that you're being polite.

Tone of voice

Yeah, I know it's obvious. So obvious many people forget it! When speaking, tone of voice is an important way of being polite. After all, you can politely say "Will you please shut the fuck up" and there's nothing polite about it, so of course content matters. But let's say you want the door opened and say fosgail an doras using a polite tone of voice. It's a bit blunt but not in itself an insult, and certainly you could say that in such a direct manner to a child or peer, without offending. So that gives us, as a first step:

fosgail	an	doras
open.2PersSing.IMP	the	door
Open the door

dùin	an	uinneag
close.2PersSing.IMP	the	window
Close the window

Using sibh

If you're using sibh (the Gaelic equivalent of vous/vosotros), you're already being quite polite in Gaelic. So, sibh would give you:

fosglaibh	an	doras
open.2PersPlural.IMP	the	door
Open "vous" the door

dùinibh	an	uinneag
close.2PersPlural.IMP	the	window
Close "vous" the window

dè	ur	beachd?
what	2PersPl.POSS	opinion
What is "votre" opinion?

Being indirect

Rather than giving a direct command, you can turn your command into a question to make it more polite. Rather than Fosgail an doras you could go with:

Nach	fosgail	thu	an	doras?
NEG.INTERR	open	you	the	door
Won't you open the door?

Am	fosgail	thu	an	uinneag?
INTERR	open	you	the	window
Can you open the window?

Or upping the ante a bit:

Nach	fosgail	sibh	an	doras?
NEG.INTERR	open	you.PLURAL	the	door
Won't "vous" open the door?

Am	fosgail	sibh	an	uinneag?
INTERR	open	you.PLURAL	the	window
Can "vous" open the window?

Or, to be even more indirect, you could refer to the fact that there's a draught, it's getting cold, or maybe that there's noise outside.

Tha	i	a’ fàs	caran	fuar	a-muigh
be	she	growing	somewhat	cold	outside
It's growing a bit cold outside.

You get the idea.

The handy words saoil and feuch

To top it all, you can combine all of the above with the words saoil or feuch which you can loosely translate as "I wonder if" and "try to" respectively. Short of curtseying, spoken with the right tone of voice, the following is about as polite as it gets:

Saoil	am	fosgail	sibh	an	uinneag?
consider	INTERR	open	you.PLURAL	the	window
I wonder if "vous" might open the window?

Feuch	am	bi	thu	nas	sàmhaich	a-nis.
try	INTERR	be	you	more	quite	now
Please try and be more quiet now!

It may seem like a lot of hard work but I find it quite pleasant that, to be polite, you have to be a lot more thoughtful about your words than just tacking on a "please" at the end. But, hard work or not, that's just the way the shortbread crumbles in Gaelic. Beir buaidh!

But in Irish...

Yes, in Irish you can use le do thoil/bhur dtoil and más e do thoil é/bhur dtoil é quite liberally today. According to the Irish Corpus, the earliest incidents of this phrase in the sense of please all seem to go no further back than the 1700s (the corpus goes back to 1600), there's a mas é bhur dtoil é in Stair Éamuinn Uí Chleire and a más é do thoil é in the 1780 Silva Gadelica. But you have to get to the 1800s for the phrase to appear in more substantial numbers.

Anyway, Irish usage is interesting but does not automatically mean that the same applies to Scottish Gaelic. They two are different languages and while they share many similarities, linguistically, culturally and historically, there are also many differences. Here's an obvious one: In Irish there is a handy generic phrase for greeting someone - Dia duit. Now while Dia dhut would be of course understandable and grammatical Scottish Gaelic, people just don't say it. Maybe they did before the Reformation (see my musings on Feasgar math or how to start an argument if you're curious) but certainly not today.