They didn't rule out coalition with the Social Democrats.

他们不排除与社会民主党人结盟的可能性。

《牛津词典》

The Social Democrats are now in alliance with the Greens.

社会民主党现在与绿党结成联盟。

《牛津词典》

The Social Democrats could still carry out their threat to leave the government.

社会民主党人仍然可能实现其脱离政府的威胁。

《柯林斯英汉双解大词典》

Although the Belgian Christian-Democrats are considered to be conservatives, they are close to the Social-Democrats, their preferred partners in government.

CENTERFORSECURITYPOLICY: Europe dumps democracy

On the other hand, these two main parties--I mean, the Social Democrats themselves and the Christian Democrats--they are basically two social democratic parties.

NPR: Merkel Claims Top Job in German Government

After all, the coalition, between her centre-right Christian Democrats and the centre-left Social Democrats, came about only because she and her party did unexpectedly badly in last September's election.

ECONOMIST: Germany's government