When introducing {HEAD ~ elements} of the embodiments of {TAIL ~ the present invention}, the articles “a”, “an”, “the” and “said” 
When introducing { HEAD ~ elements } of the embodiments of { TAIL ~ the present invention } , the articles “ a ” , “ an ” , “ the ” and “ said ”
OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH