into
prep. 到…里;深入…之中;成為…狀況;進入到…之內
The word into is a preposition that expresses movement of something toward or into something else.into是一個介詞，表示某物向另一物移動。
In toIn to, on the other hand, is the adverb in followed by the preposition to. They aren't really related and only happen to fall next to each other based on sentence construction. In to，另一方面，是副詞in後邊跟著一個介詞to。它們之間其實沒有任何聯繫，只是句子結構需要讓他倆挨到一起了。
小竅門
「Into」 usually answers the question 「where?」 while 「in to」 is generally short for 「in order to.」 So look at your sentence and replace 「into」 or 「in to」 with 「where?」 If the second half of your sentence answers it, use 「into.」 If it doesn』t, replace 「where」 with 「in order to.」 If that works, use 「in to.」
「Into」通常回答問題「where?「，然而」in to「通常是」in order to「的縮寫。所以，你可以看著你的句子，把「in to」或「in to」替換成「where」，如果句子的後半部分恰好能回答這個問題，請使用「into」。否則，請將「where」替換為「in order to」。如果句子意思通順，就是用「in to」。
比方說：
The tooth fairy put my daughter’s tooth into her pocket.
牙仙把我女兒的牙齒收進了她的口袋。
The tooth fairy put my daughter’s tooth where? Ah—into her pocket.
牙仙把我女兒的牙放到哪-哦，放到口袋裡
The tooth fairy came in to collect my daughter’s tooth.
牙仙進來把我女兒的牙收走了。
The tooth fairy came where? -collect my daughter’s tooth? Hmm … that doesn』t work.
The tooth fairy came in order to collect my daughter’s tooth.
牙仙進哪-收我女兒的牙?並不能說通。牙仙進來-為了收走我女兒的牙。