Sentence:  The Government regulations provide that the <WSD>forelight</WSD> on the large freighters shall be 40 feet above the main deck, and that the rear light shall be 15 feet above the <WSD>forelight</WSD>. 
Meaning of the word marked with <WSD> tags:  A forward positioned or forward facing light, especially one used to guide, direct, or navigate; beacon;  a signal; indicator