Text: When Lake Nasser threatened to flood the complex in the 1970s, engineers had the unenviable task of formulating a plan to save it and this they did with consummate skill.
Entailment: Engineers were able to save the complex from Lake Nasser's floodwaters in the 1970s.
Contradiction: In the 1970s, engineers tried and failed to stop Lake Nasser from flooding the complex.