Did you know that Tijuana rhymes with marijuana? Of course you did — you’ve heard Cypress Hill before. The Hill’s 1991 self-titled debut was a hip-hop landmark that altered the genre’s very structure. Within months of its release, everyone from House of Pain to Ice Cube was imitating the East Los Angeles trio. The group’s popularity peaked soon after with its sophomore offering, Black Sunday. The ensuing years, however, have not been kind; the group has wrestled with internal conflict and creative drought. The elements that once made the group so fresh (DJ Muggs’ off-kilter beats, B Real’s distinct nasal whine, Sen Dog as rap’s answer to Kevin Eubanks) have been recycled until they don’t matter anymore. Touted as a return to form, Till Death Do Us Part won’t resuscitate the corpse of this once formidable unit, though it’s better than the group’s last few efforts. “Another Body Drops” has a strident thrust, but Cypress’ fictional accounts of murder and drug running seem increasingly hard to swallow in an era when real Mexicali gangstas such as the Darkroom Familia offer eerily authentic street tales. Of course, there are plenty of songs about pot, including “Ganja Bus” and “Bong Hit,” but even Cypress seems ambivalent about packing the pipe this time around.