Quick Phrase provides a mode triggered by hot key. It can be used as a temporary mode for type English (with spell hint provided by the fcitx-spell module), as well as a Table input method which reads from a configuration file.
In some Chinese input method, it's semicolon due to historical reason, if you want to use it every where, you'd better change configuration, the hotkey in configuration is global to any input method. But hotkey world is being occupied by so many application so fcitx don't new key by default so easily, but one of candidate can be Super+Grave (`).
The file is a UTF-8 text file under ~/.config/fcitx/data/QuickPhrase.mb, if there is no such file or parent directory, create a new one (and necessary parent directory) yourself.
Browse here for more example Category:QuickPhrase.
smile （・∀・） kira (ゝ∀･) angry (￣ー￣) angry ヽ(｀д´)ﾉ cry (つД`) shock (°Д°) satisfy (￣ˇ￣) eeee 诶诶诶诶(((( ;°д°))))诶诶 frac14 ¼ frac12 ½ frac34 ¾ frac13 ⅓ frac23 ⅔ frac15 ⅕ frac25 ⅖ frac35 ⅗ frac45 ⅘ frac16 ⅙ frac56 ⅚ frac58 ⅝ frac78 ⅞
Disable it from code
If you find quickphrase conflict with your input method, you can use
boolean flag = false; FcitxInstanceSetContext(inst, CONTEXT_DISABLE_QUICKPHRASE, &flag);
in your input method Init function.