Bad tempered/Easily annoyed

·         Peevish (Adj.)

·         Surly (Adj.)

·         Splenetic (Adj.)

·         Waspish (Adj.)

·         Testy (Adj.)

·         Snappish (Adj.)

·         Crotchety (Adj.)

·         Irascible (Adj.)

·         Grouchy (Adj.)

·         Churlish (Adj.)

·         Choleric (Adj.)

·         Cantankerous (Adj.)

·         Petulant (Adj.)

·         Pettish (Adj.)

·         Grumpy (Adj.)

·         Curmudgeon (Noun)

To cause constant or repeated trouble for someone or something

·         Beset (Verb)

·         Beleaguer (Verb)

·         Plague (Noun & Verb)

Explanation:  Plague (Noun) means a disease that causes death and that spreads quickly to large number of people. Plague (Verb) means to cause continuous trouble.

To make something less beautiful or to ruin the quality of something

·         Blemish (Verb & Noun)

·         Taint (Verb & Noun)

·         Tarnish (Verb & Verb)

·         Defile (Verb & Noun)

·         Debase (Verb)

·         Sully (Verb)0

·         Besmirch

Explanation:  Blemish (or Taint) means something that causes a person or thing to be thought of as bad etc. Tarnish means thin layer on surface of metal which makes metal look dull. Defile (Noun) means narrow passage through mountain