Add punctuation: Has in the past been treated sludge for recycling
A: Has in the past been treated sludge for recycling?

Add punctuation: Two girls at the table below lower their voices
A: Two girls at the table below lower their voices.

Add punctuation: Selfadhesive paper or paperboard labels of all kinds nonprinted
A:
Self-adhesive paper or paperboard labels of all kinds, non-printed