Cognitive catatonia

Help! Swamped under with prelim grading. Dunno why it's taking so long. Maybe I'm thinking too hard and being too careful with each question, causing bouts of cognitive catatonia between answer scripts. In that kind of mental state, somnolence sneaks up like a ninja in bedroom slippers and delivers a chop to the back of the neck for the coup de grace.

Cannot. Deadline is too close to fool around. Focus. Focus...