un- + verb (indicates reversal of action)
常用于表示可以逆转的动作。
She had to undo the knot.
她不得不解开这个结。
pref. 不
先理解核心含义,再看它在真实句子里的用法。
pref. 不;不会的
An inseparable verbal prefix or particle. It is prefixed: (a) To;verbs to express the contrary, and not the simple negative, of the;action of the verb to which it is prefixed; as in uncoil, undo, unfold.;(b) To nouns to form verbs expressing privation of the thing, quality,;or state expressed by the noun, or separation from it; as in unchild,;unsex. Sometimes particles and participial adjectives formed with this;prefix coincide in form with compounds of the negative prefix un- (see;2d Un-); as in undone (from undo), meaning unfastened, ruined; and;undone (from 2d un- and done) meaning not done, not finished. Un- is;sometimes used with an intensive force merely; as in unloose.;adv. An inseparable prefix, or particle, signifying not; in-;;non-. In- is prefixed mostly to words of Latin origin, or else to words;formed by Latin suffixes; un- is of much wider application, and is;attached at will to almost any adjective, or participle used;adjectively, or adverb, from which it may be desired to form a;corresponding negative adjective or adverb, and is also, but less;freely, prefixed to nouns. Un- sometimes has merely an intensive force;;as in unmerciless, unremorseless.;adv. Un- is prefixed to adjectives, or to words used adjectively.;adv. To adjectives, to denote the absence of the quality;designated by the adjective;adv. To past particles, or to adjectives formed after the analogy;of past particles, to indicate the absence of the condition or state;expressed by them;adv. To present particles which come from intransitive verbs, or;are themselves employed as adjectives, to mark the absence of the;activity, disposition, or condition implied by the participle; as, -;---- and the like.;adv. Those which have acquired an opposed or contrary, instead of;a merely negative, meaning; as, unfriendly, ungraceful, unpalatable,;unquiet, and the like; or else an intensive sense more than a prefixed;not would express; as, unending, unparalleled, undisciplined,;undoubted, unsafe, and the like.;adv. Those which have the value of independent words, inasmuch as;the simple words are either not used at all, or are rarely, or at least;much less frequently, used; as, unavoidable, unconscionable,;undeniable, unspeakable, unprecedented, unruly, and the like; or;inasmuch as they are used in a different sense from the usual meaning;of the primitive, or especially in one of the significations of the;latter; as, unaccountable, unalloyed, unbelieving, unpretending,;unreserved, and the like; or inasmuch as they are so frequently and;familiarly used that they are hardly felt to be of negative origin; as,;uncertain, uneven, and the like.;adv. Those which are anomalous, provincial, or, for some other;reason, not desirable to be used, and are so indicated; as, unpure for;impure, unsatisfaction for dissatisfaction, unexpressible for;inexpressible, and the like.;adv. Un- is prefixed to nouns to express the absence of, or the;contrary of, that which the noun signifies; as, unbelief, unfaith,;unhealth, unrest, untruth, and the like.
She had to undo the knot.
她不得不解开这个结。
No learner guide for this sense
该词性缺少可信的词典依据,暂时无法生成学习内容。请选择其他词性。
pref. 不;不会的
An inseparable verbal prefix or particle. It is prefixed: (a) To;verbs to express the contrary, and not the simple negative, of the;action of the verb to which it is prefixed; as in uncoil, undo, unfold.;(b) To nouns to form verbs expressing privation of the thing, quality,;or state expressed by the noun, or separation from it; as in unchild,;unsex. Sometimes particles and participial adjectives formed with this;prefix coincide in form with compounds of the negative prefix un- (see;2d Un-); as in undone (from undo), meaning unfastened, ruined; and;undone (from 2d un- and done) meaning not done, not finished. Un- is;sometimes used with an intensive force merely; as in unloose.;adv. An inseparable prefix, or particle, signifying not; in-;;non-. In- is prefixed mostly to words of Latin origin, or else to words;formed by Latin suffixes; un- is of much wider application, and is;attached at will to almost any adjective, or participle used;adjectively, or adverb, from which it may be desired to form a;corresponding negative adjective or adverb, and is also, but less;freely, prefixed to nouns. Un- sometimes has merely an intensive force;;as in unmerciless, unremorseless.;adv. Un- is prefixed to adjectives, or to words used adjectively.;adv. To adjectives, to denote the absence of the quality;designated by the adjective;adv. To past particles, or to adjectives formed after the analogy;of past particles, to indicate the absence of the condition or state;expressed by them;adv. To present particles which come from intransitive verbs, or;are themselves employed as adjectives, to mark the absence of the;activity, disposition, or condition implied by the participle; as, -;---- and the like.;adv. Those which have acquired an opposed or contrary, instead of;a merely negative, meaning; as, unfriendly, ungraceful, unpalatable,;unquiet, and the like; or else an intensive sense more than a prefixed;not would express; as, unending, unparalleled, undisciplined,;undoubted, unsafe, and the like.;adv. Those which have the value of independent words, inasmuch as;the simple words are either not used at all, or are rarely, or at least;much less frequently, used; as, unavoidable, unconscionable,;undeniable, unspeakable, unprecedented, unruly, and the like; or;inasmuch as they are used in a different sense from the usual meaning;of the primitive, or especially in one of the significations of the;latter; as, unaccountable, unalloyed, unbelieving, unpretending,;unreserved, and the like; or inasmuch as they are so frequently and;familiarly used that they are hardly felt to be of negative origin; as,;uncertain, uneven, and the like.;adv. Those which are anomalous, provincial, or, for some other;reason, not desirable to be used, and are so indicated; as, unpure for;impure, unsatisfaction for dissatisfaction, unexpressible for;inexpressible, and the like.;adv. Un- is prefixed to nouns to express the absence of, or the;contrary of, that which the noun signifies; as, unbelief, unfaith,;unhealth, unrest, untruth, and the like.
She had to unlock the door before entering.
她进入之前必须先打开门锁。
The task is unfinished because we ran out of time.
任务未完成,因为我们时间不够了。
He decided to untie the knot carefully.
他决定小心地解开绳结。
常用于表示可以逆转的动作。
She had to undo the knot.
她不得不解开这个结。
这类动词通常表示去除或剥夺某物。
The king was unseated by the rebels.
国王被叛军赶下台。
Not this
This task is unpossible.
Use this
This task is impossible.
“un-”不能与形容词“possible”搭配表示否定;应使用特定前缀“im-”构成“impossible”。
Not this
I ununderstand the instructions.
Use this
I do not understand the instructions.
“un-”加在动词前通常表示相反动作(如undo),而非简单否定;否定动作时应使用助动词加not。
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