Inourclass,whenthebellrangandtheteacherclosedhisbook,itwasa
___________foreveryonetostandup.
A.signalB.chanceC.markD.measure
正确答案:A
Inourclass,whenthebellrangandtheteacherclosedhisbook,itwasa
___________foreveryonetostandup.
A.signalB.chanceC.markD.measure
正确答案:A