例句與造句

1. Since in the result of such a summation the summation index no longer appears, it does not matter which letter we use for it .
   由于在這樣求得的和的結(jié)果中，求和指標(biāo)不再出現(xiàn)，因此，對(duì)于用哪個(gè)字母來(lái)作這個(gè)指標(biāo)是無(wú)關(guān)緊要的。
2. It's difficult to find summation index in a sentence. 用summation index造句挺難的