About [[Blockly:CONTROLS IF MSG IF/ja]]
Fragment of a discussion from Translating talk:Blockly
In case of the "If-then..." block, there is an alternative to leave the keywords untranslated. Because such keywords as "if", "then", "else if", "else" and "do" are often reserved words in most of programming languages and untranslated, it might as well be left untranslated even for children. These children using Blockly will not have difficulty to remember these words in English because they will be learning alphabets and simple English in the primary schools in Japan.