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.
Fluorescent bulbs do not last forever
( z1 last :polarity - :ARG1 ( z2 bulb :mod ( z3 fluorescent ) ) :ARG2 ( z4 forever ) )