Q: This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
Following the Nice Treaty, there was an attempt to reform the constitutional law of the European Union and make it more transparent; this would have also produced a single constitutional document. However, as a result of the referendum in France and the referendum in the Netherlands, the 2004 Treaty establishing a Constitution for Europe never came into force. Instead, the Lisbon Treaty was enacted. Its substance was very similar to the proposed constitutional treaty, but it was formally an amending treaty, and – though it significantly altered the existing treaties – it did not completely replace them.
A:
When was there an attempt to reform the law of the EU?