885section C＝10

雪落无声

10.   The work of mathematician Roger Penrose in the early 1970s, on the geometry of what are called aperiodic tiles, turned out to describe the architecture of a previously unknown class of crystals.

(A) what are called aperiodic tiles, turned out to describe

(B) what is called aperiodic tiles, describes

(C) aperiodic tiles, describing

(D) so-called aperiodic tiles, describe（A）

(E) aperiodic tiles, it turned out to describe

A偶选B了

1。 what引导名词性从句，系动词由表语决定？？？

2，一项研究成果为什么不能用一般现在时？B为什么错？因为前文有明确时间in the early 1970’s 嘛？

renprince

同意你的解释