"The clothing was washed by Rehema"
Translation:Nguo zimefuliwa na Rehema
it says the clothing and not 'clothes' so we're supposed to assume it's plural? also, it says "was" and not "has been" so the -me- tense is wrong...
I agree with you on the -li-/-me- issue.
"Clothing" is a collective word, equivalent in meaning to "clothes", so it equates to the plural nguo. The singular nguo means a single item of clothing, a garment.