— Be quiet, the head teacher Mr. Gu is coming. — Don't worry. It _____ be him. Mr. Gu is much fatter.
A:mustn't
B:may not
C:needn't
D:can't
以下是四种粒子的结构示意图,结合图示回答下列问题.(1)属于同种元素的粒子是____;(填字母,下同)(2)化学性质相似的粒子是____
古罗马《民法大全》规定:……不得基于怀疑而惩罚任何人。……与其判处无罪之人,不如容许罪犯逃脱惩罚》”。这反映了罗马民法( )