Fierce words can be more harmful than you think.

An unkind person cannot be a friend.

Don't fall into the chasm.
(That is, don't fall into the trap that someone has laid for you.)

like vegetable food before a tetrapteron
(It's used in the sense of 'to go to waste.' Tetrapterons are predators and have no use for vegetable-based food. If you place vegetables before them, that food will go to waste.)

It's hard to bounce a heavy ball.
(That is, it's difficult to make someone who is stubborn or inept do what you want them to.)

Crawl, walk, run;
from level to level get better.
(The meaning is that when learning something new, you have to proceed from step to step: baby steps first, then bigger ones.)

like a thorn in the butt
(that is, something extremely annoying)

(What's wrong? What's the matter?)

(Love at first sight)

They are a slinger (together).
(Calling two people a slinger praises how well they work together and complement each other.)

If you hesitate doing something, it might not be important to you.
(Of course, we often hesitate with things that are in fact important to us, because we're afraid to fail. So this proverb is more meant/used as a motivation for someone hesitating, or even as a teasing to get someone into action)

(Like) a tapirus in the clouds
(“Fish out of water”; something or someone out of their usual element or comfort zone.)

Like a slinger without a head
(Like a slinger without a head—i.e., completely lost.)

Only sleep if you are familiar with the Thanator.

One can't hang by a tail.

Slow tail!
(That is, “Don't get angry.” When the Na'vi get angry, their tails whip around, so “slow down your tail” is another way to say calm down.)

A coward commands from the canopy.

A fool jumps onto a thin vine.

Hexapede in a storm
(a metaphor or simile representing extreme panic, anxiety or timidity.)

an animal cry in the forest
(Old news)

A mantis doesn't whistle.
(Don't expect someone to do something that's not in their nature.)

(All's well that ends well).

The tail and ears also speak.
(The idea is that someone's words might not match their attitude, expression, behavior, etc.)

an expression of love.
(It's a set phrase used when giving a gift to a loved one or making a gesture of affection like a kiss or caress.)

He steps on tails.
(I.e. He is socially awkward.)

An old person's face doesn't hide their age.
(That is, Some things can't be covered up.)

The hunter hesitates and the hexapede escapes.
(Proverbial expression. Cf.: “He who hesitates is lost.”)

More helpful actions lead to less troubling outcomes.

Lack of awareness is (a form of) weakness.

(like) a fan lizard in gel
(The sense is one of being in an environment where you're prevented from acting naturally or doing what you want to do.)

(like) a touched helicoradian
(The analogy is used to indicate extreme shyness.)

Whether you succeed or not, the attempt has value.

What do we do now?

To aim is not enough; one must release the arrow.
(Intent is not enough; it's action that counts.)

One butt can't sit on the backs of two direhorses.
(You can't take both positions or sit on the fence; you need to decide.)

You can't kill a great leonopteryx by constricting its throat.
(Proverbial expression for a method that will not work.)

Happy only!
(Na'vi toast)

before the hellfire wasp stings
(as quickly as possible)

Proper action, bad result.
(Said when something that should have turned out well didn't. Can include the idea, “Well, my/our/your/his/her/their heart was in the right place.”)

(If you can't be flawless, at least be brief.)

(Great minds think alike.)

(take care, travel safely.)

(take care, travel safely.)

(don't worry (about it))

Good luck!

Ask a thanator to release its prey.
(Refers to a futile gesture, an attempt to achieve something that might be desirable but will clearly not happen. In conversation it's usually shortened to Ätxäle pa(lu)lukanur.)

Strong and happy!
(That is, may you derive strength and happiness from this event, accomplishment, etc.)