He is rather difficult to make friends w
题型:选择题
问题:
He is rather difficult to make friends with, but the friendship of his, _____, is truer than any other.
A.once gained
B.when to gain
C.after gained
D.while gaining
He is rather difficult to make friends with, but the friendship of his, _____, is truer than any other.
A.once gained
B.when to gain
C.after gained
D.while gaining