One thing after your plug your USB, check your port with follow
ll /dev/tty*
if you can see my port as ttyUSB0 or with difference name (i.g ttyUSB* / ttyACM* ).
and then try to compile your sketch with following,
cd /path/your/arduino/installation/
$ARDUINO-DIR(pwd)
cd /path/your/sketch/
$ARDUINO-INO/arduino --verify sketch.ino --board arduino:avr:uno --port /dev/ttyUSB0 --verbose //compile your sketch.ino with arduino uno board.
Hope this helps.