Improve the highlighted part of the sentence given below.
During his long discourse,he did not $touch$ that point.

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$His\, powerful\, desire$ brought about his downfall.

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Why the dinosaurs died out $is\, not\, known.$

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Other countries $have\, eradicated$ this disease ten years ago.

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The demonstration $passed\ off$ peacefully.

Improve the highlighted part of the sentence given below.
The logic of the Berlin Wall $already\, had\, been\, undermined$ but when the news came through that the wall itself had been opened,$I$ jumped into a car.