Keep Death off the Roads is a 1945 public information film that is viewable online here. At first glance it appears to be cel animation using an unusual white silhouette style, but on closer inspection most of it looks to have actually been made using paper cut-outs. The film isn't listed in Gifford's filmography, although a 1946 Halas & Batchelor film by the name of Road Safety is; it's possible that they are the same.
"Not so long ago, we learned to protect ourselves from the dangers overhead. Now this is over, but there still remains the danger on the ground, claiming many victims."
"Mrs. Brown has done her shopping, queued and argued and smiled. Now she's carrying home the result of the morning's work."
"Look out there! That lovely meal she was dreaming of cooking for the family is gone, but she was very lucky not to have been injured. Do remember: crossing a road needs all your concentration and care."
"Very nice, Johnny, but how much safer you'd be on the pavement or in a playground."
"A bicycle isn't at all under control when ridden freehand. What would you do in an emergency?"
"You see - the unexpected does happen, and you are just as much to blame as Johnny."
"The bus was late and now you're in a hurry. A look to the right and a look to the left takes only two seconds more."
"But now it will be some weeks before you can attend to the urgent business."
"Don't forget, it takes two to make an accident. A little more care on the part of every road-user would mean less tragedies. Keep death off the roads."
As an aside, a variation of the same slogan was used decade and a half later in a 1960 film entitled Take Death off the Roads.
"Take D, E, A, T, H off the roads..."
"And make our roads safe."
"Be a better driver."
Both shorts can be found across the two-part Charley Says DVD release.