- 1想必、無疑
You use doubtless when you want to say that something is almost certain — you are very sure, or you want to sound sure. It often sits before the main idea: “Doubtless they will come,” or after the person: “She will doubtless be late.” Though actually, it is not as hard as “no doubt at all.” Speakers often use it when they feel almost sure, or when they want to sound calm and certain, even if a little room for surprise is still there. It is a little formal and a little old-fashioned; in easy talk people more often say “I’m sure,” “probably,” or “no doubt.” There is also an older adjective use, “a doubtless fact,” but you will almost always meet it as this “almost certainly” word. It does not mean “I have doubts.”
From the word’s history
From Middle English douteles; doubt + -less.
doubt（懷疑）加 -less（沒有）：毫無疑問。
組成doubt + -less: “without doubt,” though in real talk it often means “almost certainly,” not “zero doubt.”
同家族的字
- doubtthe same “not being sure” word that doubtless is built from
- doubtfulfull of doubt — the opposite feeling
- undoubtedlyanother “almost no doubt” word built from the same doubt
原始詞典資料3 筆記錄
以下是外部詞典記錄的用法，摘錄並精簡格式，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
doubtlessadj/ˈdaʊ̯tləs/
- 1
Characterized by or experiencing no doubt at all, certain; undoubted; undoubting.
- There are those who have doubtless faith in revelation.
- It is doubtless that the old reprobate who sued for his daughter's hand heard some unsavory truths from the man.
- 2
obsoleteFree from fear or suspicion.
- And, pretty childe, ſleepe doubtleſſe, and ſecure, / That Hubert for the wealth of all the world, / Will not offend thee.
doubtlessadv/ˈdaʊ̯tləs/
- 1
Without doubt; certainly; definitely; very probably, in all likelihood; doubtlessly.
- […] And, doubtless, unto thee is given A life that bears immortal fruit In such great offices as suit The full-grown energies of heaven.
- I cannot remember that I spoke a word, though doubtless I did.
摘錄自 英文維基詞典 English Wiktionary，已精簡格式；依 CC BY-SA 4.0 授權使用，改動後的內容同樣以此授權提供。