Here’s the match.

Source (Chinese)

• 列宁：《两种策略》（1905年2月1日〔14日〕以前）—中文译文见马克思主义文库（MIA）中文站与《列宁全集》中文第九卷的同一段落：
  “这种变革，随着农奴制的崩溃，已在俄国开始了，正因为我国的政治上层建筑落后于已经实现的社会关系变革，才使上层建筑的倾覆成为必不可免。” www.marxists.org

Corresponding English on MIA

On the MIA English site (Lenin, “Two Tactics”, dated February 14, 1905), the matching sentence appears as follows (excerpt):

“This revolution began in Russia with the abolition of serfdom, and it is the backwardness of our political superstructure as compared with the accomplished revolution …” www.marxists.org

(The sentence then continues to say that this lag “makes the collapse of the superstructure inevitable,” and even an immediate collapse “as the result of a single blow” is possible. You can find it on the linked page—search for serfdom.) www.marxists.orgBibliographic note: The English page is an MIA transcription; the same passage is also in Lenin’s Collected Works, Vol. 9 (see the work’s index page). www.marxists.org