Add punctuation: During two or three days they slowly careered round in the air in an immense ellipse at least five or six miles in diameter and at night alighted on the taller trees which were completely coated with them
A: During two or three days they slowly careered round in the air in an immense ellipse, at least five or six miles in diameter, and at night alighted on the taller trees which were completely coated with them.

Add punctuation: The addition of a greenhouse gas which absorbs in both bands would then increase the absorption in the unsaturated band but not in the saturated band
A: The addition of a greenhouse gas which absorbs in both bands would then increase the absorption in the unsaturated band but not in the saturated band.

Add punctuation: Then she said Here is my servant Bilhah go in to her so that she may have a child on my knees and I may have a family by her
A:
Then she said, Here is my servant Bilhah, go in to her, so that she may have a child on my knees, and I may have a family by her.