Whenapencilispartlyinaglassofwater,itlooksasifit______.
A.breaksB.has broken
C.were brokenD.had been broken在线课程C
as if 引导的句子，有时用虚拟语气，有时不用。原则上说，若指事实或可能为事实，不用虚拟语气；若指现在，从句谓语动词用一般过去时（be 用 were）；若指过去用过去完成时，若指将来用过去将来时或用 were to do sth.