Sometimes, writers summarize and correctly document their sources, but the summaries are too similar to the original: phrases and groups of words from the original text might not be rewritten in the writer's "language" but retain too much of the original author's style. This is often tricky but is still considered plagiarism.
The following is an article taken from the Disciple magazine. While Example I seems to be a good summary, the summary strays over the line into quotation. Example II is an acceptable summary of the article.
"Reformed Church Would Set Precedent with NCC, Evangelical Group Memberships"
The Reformed Church in America has voted to become the first denomination to seek membership in both the National Council of the Churches of Christ in the USA and the National Association of Evangelicals, signaling what the NAE hopes will be a new era in ecumenical cooperation.
A Bylaws change earlier this year ended the NAE prohibition that prevented members from holding membership in the NCC, which is comprised mostly of mainline Protestant churches.
Meeting in Hempstead, NY, for its annual General Synod, the 259,651-member denomination voted to seek membership in the NAE as a way of maintaining ecumenical relations while also stressing its evangelical nature.
Example I-unacceptable summary
Signaling a new era in ecumenical cooperation, the Reformed Church in America has voted to become members in the National Council of Churches of Christ in the USA and the National Association of Evangelicals. The 260,000 members decided to do this as a way of maintaining ecumenical relations while stressing the evangelical nature of the church.
This is an unacceptable summary because there are several phrases that are identical to the original.
Example II-acceptable summary
In its annual meeting in Hempstead, NY, The Reformed Church in America has decided to pursue membership in two organizations: the National Council of Churches of Christ in the USA and the National Association of Evangelicals. It is the first denomination to request membership in both organizations. The RCA's approximately 260,000 members want to become part of both groups in order to encourage ecumenism while continuing to stress their evangelic character.
This is an acceptable summary because it summarizes the article without using phrases from the original.