letters will cost a little more,but they will certainly travel faster.

问题描述:

letters will cost a little more,but they will certainly travel faster.

much/many的比较级是more, 意思是:更多的;更高程度的
He has more chance than ever.
他从来没有这样的大好机会.
letters will cost a little more,but they will certainly travel faster.
信件将会花费得多一点,但当然会递送得更快些