TRSE: How To Draw Tutorials:
Emotions:

Sadness, Sympathy:
"How could you.......?!" -Moon-

  A person like Sailor Moon do tend to cry a lot like a baby, but this picture of Moon shows that she's crying because she's undergoing the psychological pain within her as if her heart has been broken, someone said plenty of bad things about her in her face, or someone else dear to her has been hurt.
Jupiter is shaking with multiple emotions.

  This would be typical of a character undergoing multiple emotions at the same time.  Sometimes, trembling lower lip accomplay the face when crying.
"There're nothing we can do about them" -Neptune-

  When one is sad or sympathetic, the muscles in the face depress giving a down-turned mouth, and furrowing eyebrows.
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Annoyed/Irritiated/Frustrated
Pluto gets annoyed that her important advice was ignored.

 
"HMPH!" -Neptune-

  Sometimes, a person would go "HMPH!" when annoyed which is usually accompanied by a puff of air.
"Leave her alone!" -Mars- (protecting Moon)

  That's the way of snapping back at someone when annoyed/irridiated.
"That's it! I'm taking the Luna Pen away from her!" -Luna-

   Luna's very frustrated with the Moon using the Disguise Pen for very frivolous reasons.

Anger:
  This is a common example of anger. Usually accomplished by "pulsing blood veins" that looks like three crooked lines (sometimes four) that are parallel to each other, and sometimes steaming (as if her head got hot).
   This is an example of controlled anger. Neptune was angry at Mercury for her failure to stop a villian, and started lecturing Mercury using her anger as a means of making her point.
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Insulted
   That is an example of how a person react to an insult that scored a direct hit on that person. I tend to use a "pain" star  to indict that a person has been insulted ("a slab in the heart").
"DUMB?! BRAT?! PESTERING?! Why you.......!" -Venus being insulted by a villain.
   Another example of being insulted, but on more severe scale.

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