Which of the following is a digraph?
(A) the letters 'fr' in free.
(B) the letters 'ng' in sing.
(C) the letters 'st' in street.
(D) the letters 'nd' in bend.
digraph
二合字母(如th)
合體字母(如æ)
Which of the following is a digraph? (..-阿摩線上測驗