What is the pronunciation of "が,ぎ,ぐ,げ,ご" when they're not coming first of a word? My text book says there is a rule of the pronunciation of が,ぎ,ぐ,げ,ご which is that when they come first of a word, they're pronouced as "ga, gi, gu, ge, go" but when not, the "g" part pronunciation change into "n" in "going"(the / η /), they would be pronounced as "ηa, ηi, ηu, ηe, ηo". Like 学生 is pronounced "gakusei" because が comes first of the word, whereas はがき is pronounced as "haηaki" not "hagaki" , かぎ is as "kaηi" not "kagi", 仕事 is as "shiηoto" not "shigoto" because in these case the が,ぎ,ご are not coming first of these words. However, that's written in my text book. The thing is, I still hear many Japanese people just pronounce はがき as "hagaki", かぎ as "kagi", 仕事 as "shigoto",not as "haηki", "kaηi", "shiηoto", etc. So I'm confused which one is the standard pronunciation of が、ぎ、ぐ、げ、ご when they're not coming first of a word? Thanks in advance!