When the members of a compound sentence are complex or contain commas.
Franklin, like many others, was a printer; but, unlike the others, he was student, statesman, and publicist as well.
With ten per cent of this flour the bread acquired a slight flavor of rye; fifteen per cent gave it a dark color; a further addition made the baked crumb very hard.
The meeting was composed of representatives from the following districts: Newton, 4 delegates, 2 substitutes; Dorchester, 6 delegates, 3 substitutes; Quincy, 8 delegates, 4 substitutes; Brookline, 10 delegates, 5 substitutes.
2.

When the members of a compound sentence contain statements distinct, but not sufficiently distinct to be thrown into separate sentences.
Sit thou a patient looker-on; Judge not the play before the play be done; Her plot has many changes; every day Speaks a new scene.

The last act crowns the play.
3.

When each of the members of a compound sentence makes a distinct statement and has some dependence on statements in the other member or members of the sentence.
Wisdom hath builded her house; she hath hewn out her seven pillars; she hath killed her beasts; she hath mingled her wine; she hath furnished her table.
Each member of this sentence is nearly complete.

It is not quite a full and definite statement, but it is much more than a mere amplification such as we might get by leaving out _she hath_ every time after the first.