*what a female is named, when they have a tough outer shell, but a tender inner being, closer to when we call a tough looking person a big softie*
It'll sound different depending on what 仮名 follows it(such as in the words
Another use for the 促音 is at the end of a sentence to signify a sudden stop in both speech and pronouncing a 仮名 with a full breath, examples including but certainly not limited to when you see something that rends you speechless or being punched in the stomach. This usage is one you're more likely to see in 漫画 and アニメ, but you also can also use to write out any reactions you may have to events that make you do a double take.
For example, you get to the front of a concert line, only to find they've just sold out. I would imagine the immediate reaction would be "あっ" followed by despair.
Lastly, it serves to add an emphasis on a word when spoken, much like how someone say "Amazing" they put an emphasis on the "ma" portion, producing "Ama~zing". Often seen when using the word ばかり(thus rendering as ばっかり) but can also apply to others as deemed appropriate.
Small note: with m and n sounds it's a bit different, as ん proceeds these instead of a small つ to produce the desired affect, such as with the word あまり(which you'll learn about down the line) being rendered as あんまり. To produce a 促音 (as well as a smaller version of あ, い, う, え, お, や, ゆ, or よ)on the computer, type x, then the 仮名 you want.
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