ASSEMBLYYY!!!!!

1.VINDICTIVE

adjective: to have a very strong desire for revenge

Though the other girl had only lightly poked fun of Vanessa's choice in attire, Vanessa was so vindictive that she waited for an entire semester to get the perfect revenge.

2.PUGNACIOUS

adjective: eager to fight or argue; verbally combative

The comedian told one flat joke after another, and when the audience started booing, he pugnaciously spat back at them, “Hey, you think this is easy – why don’t you buffoons give it a shot?”

3.FICKLE 

adjective: liable to sudden unpredictable change, esp. in affections or attachments

She was so fickle in her politics, it was hard to pinpoint her beliefs; one week she would embrace a side, and the next week she would denounce it.

4. SANGUINE 

adjective: cheerful; optimistic

With the prospect of having to learn 3,000 words during the course of the summer, Paul was anything but sanguine.

5. DEVOLVE

verb: pass on or delegate to another

The company was full of managers known for devolving tasks to lower management, but never doing much work themselves.

verb: grow worse (usually "devolve into")

The dialogue between the two academics devolved into a downright bitter argument.