| double-dealing |
| duplicity |
| duty(noun, interest, issue, responsibility, problem) |
| enterprise(noun, activity, matter, contract, deal) |
| execution(noun, activity, matter, contract, deal) |
| exercise(noun, action, movement, measure, undertaking) |
| exertion(noun, action, movement) |
| experience(noun, time, event, thing, case) |
| experiment(noun, action, measure, exercise, undertaking) |
| extracurricular activity(noun, expression, relationship, liaison) |
| extramarital affair(noun, relationship) |
| fling(noun, thing, relationship, liaison) |
| foolishness |
| function(noun, interest, issue, responsibility, problem) |
| funny business |
| go(noun, time, thing, case, juncture) |
| go down(expression, contingency, probability) |
| grievance(noun, trouble, worry, difficulty, problem) |
| happenings(noun, activity, activities, affairs, carryings-on) |
| high jinks(noun, expression, activity, affairs, carryings-on) |