Why do you need translation comments?
Consider this simple case; you have a menu item called “Manual”. You know what it means, but when the translator sees this they will wonder did you mean:
This is the simplest case where a translation comment such as “The installation manual” helps to clarify the situation and makes a translator more productive.
Real world examples are best. This is a discussion over the use of the word “Forward” in Northern Sotho:
“When you go forward. You go ‘Pele’, But when you forward the document, O ‘Fetišetša pele’, so if you just say forward, we don’t know what you are talking about, it is better if it is in a sentence. But in this case i think we will use ‘pele’ because on the string no:86 and 88 there is “show previous page in history” and “show next page in history”
Was there translators guess correct? I think so, but it makes it so much easier if they don’t need to be super sleuths as well as translators.
Words that can be used as a noun or verb in English but may have different names in another language
Is it really obvious that TERM should not be translated?
Filenames that you do not want translated eg .Xauthority. Especially if they appear translatable.
Some sentences do not make it clear that the text refers to a program name which you probably don’t want to translate.
Especially when they appear as URIs eg help:index. Also protocol responses eg. “Server returned HELO” very tempting to translate. Or “KEEPALIVE response”. Should KEEPALIVE be translated?
The types of comments depend very much on the localisation system implemented:
The appear to the translator like this:
msgid ""
"_: The installation manual\n"
"Manual"
One advantage is that they can double as context strings. In Gettext PO files you can only have one translation of the source English word. So if your language translates an English word differently depending if it is a noun or a verb then you will have a problem. Context information in a KDE style comment essentially means that the strings are different and thus allows you to distinguish between verb and nouns spelled the same way in English.
These appear in the # comments of a message block. They are sometimes overlooked by translators as usually the PO editing tool does not make them obvious.
FIXME not sure how to do it please refer to the Gettext manual and KDE programmers manual