This sentence should be underlined.

This sentence should be overlined.

This sentence should be stricken out.

This sentence should be blinking (if the UA supports that).

The sentence should be underlined. This sentence should be underlined.

This sentence should be underlined and overlined.

This sentence should be underlined, overlined, and stricken.

There should be no red at the end of this line.  

There should be no red at the end of this line.FAIL: Images required. 

This sentence and all its images FAIL: Images required. FAIL: Images required. should be underlined.

There should be a long blue underline between here: FAIL FAIL FAIL FAIL :and here.