Related Clues:

• Tough march
• "Bubble, bubble, __ and trouble ..."
• March through mud, e.g.
• Work wearyingly
• Wade knee-deep
• It might make you a sweater
• ''Double, double ___ and trouble . . .''
• ''Macbeth'' witches' word
• Make slow progress
• Trouble partner
• Trudge (through)
• Tiresome task
• "Macbeth" witches' word
• Chinese money
• Trudge through sludge, e.g.