The troll language have many symbols that mean very little on their own. This is why trolls use the body language and sounds together to make a "sentence". The typical Troll sentence consists of one or more sounds and at least one form of body language. Another way of saying this is "use of conjunction ".
For example, if the alphatroll made a moderate grunt with a point towards a troll , it's likely he wants that specific troll to be banished from the tribe.
Here's a cheat sheet to help you with translation.
Loud Grunt- Warning about the troll or tribe
Moderate Grunt- Long journey or banishing
Short Grunt- Asserts dominance
Loud Grunt- Troll is aggressive
Medium Grunt- Troll's anger is rising
Quiet Grunt- Troll is passive
Angry Roar- Battle Cry
Happy Roar- Acceptance
Sad Roars- Greif and Mourning
Scared Roars- Call for help
Pointed Up- Upcoming weather
Pointing Down- Obstacles or halts
Pointing Straight- Goal to meet
Pointing Anywhere- Draws Attention
Shaking Head- Changes
Jittering- Mental, Physical, or Emotional Pain