1. There are many fluorescent lights on the ceiling.

2. There are many fluorescent lamps on the ceiling.

3. There are many fluorescent light bulbs on the ceiling.

(Which expressions are right? Which one is commonly used? Thank you.)

Use #1 ... it's the best.

Lamps are usually those that stand on the floor or sit on a table.
http://www.houzz.com/photos/floor-lamps
and
http://tablelamps7650.wordpress.com/2010/12/29/how-to-buy-table-lamps/

That TV is crap. I bought mine in 2008 for $400 at Sams Club. They said it werokd but just needed a new bulb. I spent $140 at the time for it. Picture was great, my bulb went out on me within 9 months. Because $140 for a new bulb was cheaper than a new tv, I bought another one. I ended up buying two bulbs after that one and my last one blew this past September. HP discontinued this TV and the bulbs are no longer produced so they cost about $200 a pop now.I called HP and complained that I wasn't getting the life out of this bulb as advertised and they did nothing about it, no discount or no free bulb. I said to hell with this and used my standard tube TV. DO NOT PUT MORE MONEY INTO IT. Its defective. I'm buying a brand new HDTV in a couple weeks so I can finally put that failure of a set behind me.Good luck.

All three expressions are grammatically correct and can be used to describe the presence of fluorescent lighting fixtures on the ceiling. However, there are subtle differences in their usage and meaning:

1. "There are many fluorescent lights on the ceiling."
This sentence is commonly used and accurately conveys the idea that there are multiple fluorescent lighting fixtures installed on the ceiling.

2. "There are many fluorescent lamps on the ceiling."
This sentence is also grammatically correct, but the word "lamps" might be less commonly used in this context. "Lamps" generally refers to portable lighting devices that can be moved or placed on surfaces like tables or desks. While it is not incorrect to use "lamps" to describe ceiling fixtures, "lights" is more commonly used.

3. "There are many fluorescent light bulbs on the ceiling."
Similarly to the previous example, this sentence is grammatically correct, but the use of "light bulbs" can imply individual bulbs rather than the fixtures themselves. "Light bulbs" typically refers to the actual glass or plastic bulbs that produce light when connected to the appropriate electrical supply. So, while it is not inaccurate, it suggests a slightly different focus.

In summary, the most commonly used and direct expression would be "There are many fluorescent lights on the ceiling."