| fall off(verb, expression, fail, weaken, degenerate) |
| flag(verb, fail, weaken, degenerate, deteriorate) |
| get the better of(verb, expression, idiom, rub, grind) |
| getting worse(verb, expression, lessen, degenerate, deteriorate) |
| go downhill(verb, expression, decline, fail, weaken) |
| going bad(verb, expression, lessen, degenerate, deteriorate) |
| grind to a halt(expression, idiom, decline, idle, languish) |
| grow moldy(expression, rot, decompose, molder) |
| harass(verb, rub, grind, fray, erode) |
| irk(verb, rub, grind, fray, erode) |
| lapse(verb, fail, weaken, degenerate, deteriorate) |
| lose value(verb, expression, fail, weaken, degenerate) |
| lower(verb, fail, weaken, degenerate, deteriorate) |
| mildewed(verb, lessen, degenerate, deteriorate, wane) |
| pester(verb, rub, grind, fray, erode) |
| pine(verb, fail, weaken, degenerate, deteriorate) |
| rankle |
| recede(verb, fail, weaken, degenerate, deteriorate) |
| reduce(verb, rub, grind, fray, erode) |
| relapse(verb, fail, weaken, degenerate, deteriorate) |