How to test fluorescent bulbs<br>Look for dark areas at the base of the bulb. When bulbs age and have been used for a long time, brown spots will appear. If darkness begins to form at the ends of the tube, the bulb may be near its end.
The bulbs have a long light life when there is dark areas that form at the ends of the tubes.
( z1 live :ARG0 ( z2 bulb ) :ARG1 ( z3 light ) :ARG1-of ( z4 long ) :time ( z5 form :ARG1 ( z6 area :ARG1-of ( z7 dark ) ) :location ( z8 end :part-of ( z9 tube ) ) ) )