有into與否有何分別？

先講 "into" 這個介詞。基本上有兩個解釋；1.進入 - I saw him run into the shopping mall.我看見他跑進那購物商場。I walk into the kitchen and cook.我步入廚房煮飯。2. 變成/成為 - The liquid changes into solid quickly. 那液體很快變成固體。
個人覺得在 written English 第一句made him into a better student 會完整一些。另他成為一個更好的學生。
至於第二句，基本上 meaning 無變，但比較口語化一些。

1. make somebody into something (phrasal verb) = change/turn somebody into something

made him into a better student = 把他改變成一個更好的學生

2. make somebody something (make + object + noun)
a. to prepare/create something for somebody
e.g. Mary made us a cake.
b. to elect or choose somebody as something
e.g. He made Mary his assistant.

made him a better student = 推選他為一個更好的學生

Sentence (1) sounds more natural and reasonable, whereas sentence (2) does not make much sense.