Why are some sounds in the words when spoken, not heard?

Sometimes I hear unpronounced sounds!?!?

There is a question I often hear from learners who have started learning Japanese.

They ask, “Why are some sounds in the words when spoken, not heard?” 🤔

“Like, Ga-ku-sei (student) is always pronounced [Gaksei] when spoken” 🥹

This is a good question, you have noticed the native pronunciation!

If pronounced slowly at normal pace, it still can be understood.

However if pronounced as above, this will make you sound more natural like a native speaker who speaks fluently. 😁

Today, I would like to answer this question that you are interested in.

Let me get straight to the point, this is part of the linguistic features in Japanese phonetics. 🗣️

When the vowels “い[i]” and “う[u]” are placed under certain conditions, a phenomenon occurs in which they are not pronounced.

This phenomenon occurs in various languages, affecting pronunciation for the sake of ease and efficiency in speech.

There are two rules by which this phenomenon happens. 👐

①When い[i] or う[u] are sandwiched between these sounds (consonant k, s, t, h, f, p).

In other words, when any of these sound (き[ki], く[ku], し[shi], す[su], ち[chi], つ[tsu], ひ[hi], ふ[fu], ぴ[pi], ぷ[pu]) connect with these sounds (consonant k, s, t, h, f, p), the vowel of the first consonant tends not to be pronounced.

For example

えんぴつ Pencil ✏️： enp[i]tsu

すし Sushi 🍣：s[u]shi

がくせい student 🧑‍🎓：gak[u]sei

②When い[i] or う[u] comes at the end of a word after these consonant (consonant k, s, t, h, f, p). To put it differently, き[ki], く[ku], し[shi], す[su], ち[chi], つ[tsu], ひ[hi], ふ[fu], ぴ[pi], ぷ[pu], when any one of these sounds comes at last in the vocabulary, the vowel of that consonant tends not to be pronounced.

For example

えんぴつ Pencil ✏️ : enpits[u]

うち Home 🏠 : uch[i]

くつ shoes 👞 : kuts[u]

Of course, if the above two rules are met at the same time, both may apply!

えんぴつ Pencil ✏️： enp[i]ts[u]

すし Sushi 🍣：s[u]sh[i]

くつ shoes 👞：k[u]ts[u]