What does your father _____ Sundays?[ ]
A. do in
B. do on
C. does at
D. does on
答案:B
比Ar原子核电荷数少1且有相同核外电子数的粒子是( )
A.F-
B.S2-
C.K+
D.Cl-
近体诗的格律要求有()
A.句数固定
B.押韵严格
C.讲平仄
D.讲对仗