He could speak a little English when he was a child,but now he __ forget much.A.canB.mustC.shall

题目

He could speak a little English when he was a child,but now he __ forget much.A.canB.mustC.shall
单选及原因

答案

He could speak a little English when he was a child,but now he 【must】 forget much.
他还是个小孩的时候,还能说一点点英语.但是现在他肯定大部分已经忘记了.
but有转折,加上后面forget much,那么推测句子要说的意思是“他肯定大部分已经忘记了.”
can,能够,能够忘记,不对
shell 将会忘记,也不对
must 肯定忘记了,正解,must 表示非常肯定的猜测