Everybody should know it that malnutrition causes weakness. (Use passive voice)

It should be known by everybody that malnutrition causes weakness.

Passive voice is a grammatical construction where the subject of the sentence receives the action of the verb. In the original sentence, 'Everybody' is the active subject performing the action of 'knowing'. To transform it into passive voice, the object 'it' becomes the new subject.

The structure for converting a sentence with a modal verb (like 'should') into passive voice is modal + be + past participle of the main verb. Thus, 'should know' becomes 'should be known'. The original subject 'everybody' is then introduced as the agent using 'by everybody', although it can often be omitted when the agent is general.

The clause "that malnutrition causes weakness" functions as a noun clause, providing further information about 'it'. This type of subordinate clause typically remains unchanged when the main clause containing it is converted to passive voice.