haha.這個fighter's問題我知道答案。幾年前我感到迷惑過，後來就淡定了。

這個問題我知道答案。幾年前我感到迷惑過，後來就淡定了。

In American English , A "t" in the middle of a word like LATTER, PARTY, and LITTLE can be pronounced as a soft " d ", the d sound like the d in LADDER, HARDY, and MIDDLE.

this sound usually occurs between vowels(especially before an unstressed vowel ), between r and a vowel, or before a syllabic /l/. THe word "FIGHTING" belongs to the 1st case with yellow highlight.

I'm happy that not all Americans pronounce this way, so the rule is not consistent.
I'm lazy and dumb. In all cases, I usually pronounce t as t sound, no change. but sometimes I do change some t to d sound without being aware of the changes:)