區別：used to do sth.過去常常做某事,(意思現在不做了)。be used to doing sth / be used to sth .是指習慣於做某事.(這裡的to 是介詞.)1、used to do解釋成“過去常常做某事”，後面接動詞原形。比如說：I used to play basketball.我過去常常打籃球。2、am/is/are used to doing解釋成“現在習慣做某事”。比如說：I am used to playing basketball.我習慣打籃球。3、was/were used to doing解釋成“過去習慣做某事”。比如說：I was used to playing basketball.我過去習慣打籃球。4、be used to do解釋成“被使用去做某事”。比如說：The water is used to drink. 水被喝。擴充套件資料（語態）動詞和參與此動作的主語之間關係的一個術語。當主語是動作的發起者（或之一）時，稱為主動語態；如果動詞不定式的邏輯主語是這個不定式所表示的動作的承受者，不定式一般要用被動語態形式。如：It"s a great honour to be invited to Mary"s birthday party.（不定式作主語是被動語態to be invited是被邀請）It was impossible for lost time to be made up.（不定式作主語）I wish to be sent to work in the country.（不定式作賓語）Can you tell me which is the car to be repaired?（不定式作定語）He went to the hospital to be examined.（不定式作狀語）My work is to clean the room every day.（不定式作表語）在There be結構中，修飾主語的不定式可用被動，也可用主動。如：There are still many things to take care of (to be taken care of).但有時兩種形式表達的意思不同，如：There is nothing to do now.( We have nothing to do now.) There is nothing to be done now.(We can do nothing now.)