For example, if {HEAD ~ a user} is on a voice call using {TAIL ~ a cellular telephone}, the cell phone might not be equipped to handle video content 
For example , if { HEAD ~ a user } is on a voice call using { TAIL ~ a cellular telephone } , the cell phone might not be equipped to handle video content
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH