Solution

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4 clues

Hard journey

Word class: Common noun
Nature of clue: Synonym
Difficulty: Easy
Sources: Boatload Puzzles

Plod

Word class: Verb
Nature of clue: Synonym
Difficulty: Very easy
Sources: Boatload Puzzles

Trudge

Word class: Verb
Nature of clue: Synonym
Difficulty: Very easy
Sources: Boatload Puzzles

Other solutions to Trudge

Walk heavily

Word class: Verb
Nature of clue: Description
Difficulty: Very easy
Sources: Boatload Puzzles

Other solutions to Walk heavily

Words are categorized by artificial intelligence: there can be mistakes.