guard against

防止

gruff, gruffly, gruffness, grumble, grumbler, grummet, grumpily, grumpiness, grumpy, grunt, gruyere, gryphon, GT, Guam, guano, guarantee, guarantee against, guarantor, guaranty, guard, guard's van, guard-rail, guarded, guardhouse, guardian, guardian angel, guardianship, guardroom, guardsman, Guatemala, guava, gubernatorial, gudgeon, guelder rose, guerrilla, guerrilla (also guerilla), guess, guesser, guesstimate, guesswork,