查询词典 if and only if

A topological space is an minimal CH space if and only if each open CH-filterbase with only one adherent point converges to this point.

4拓扑空间 X是极小 CH空间，当且仅当对任意的 x∈X和任意开 CH滤基μ，若{ x}=∩U∈μU=∩U∈μcl U，则μ是 x的一个邻域基。

This logical implication that perception of meaning is only possible if and only if the indefinite is included within the perception is the reason why the 19th century dream of a consistent and complete axiomatic system with only well defined empty signs had to fail (see more about that in my article, The Loop Logic).

这一逻辑隐含的意义是唯一可能的观感只要是无限期的观感是列入19世纪梦之所以一贯和明确的，只有彻底公理化体系空迹象已经失败(多看看，我在文章河套逻辑)。

Brown and Halmos [3] showed that the only compact Toeplitz operator on the Hardy space is the zero operator and a Toeplitz operator is bounded on the Hardy space if and only if its symbol is bounded.

Brown和Halmos[3]证明了经典Hardy空间上只有零算子才是紧的Toeplitz算子，并且证明了Toeplitz算子有界等价于它的符号是有界的。

We will prove that the only compact dual Toeplitz operator is the zero operator, and that a densely defined dual Toeplitz operator with square integrable symbol is bounded if and only if its symbol is essentially bounded.

首先，我们证明了只有零算子是紧的对偶Toeplitz算子，同时给出了以平方可积函数为符号稠定义的对偶Toeplitz算子有界当且仅当它的符号函数是本性有界的。

In section 2 ,if one Lie colour algebra can be decomposed to direct sum of two ideas ,the same as the center.And when the center is zero , the derivation and the inner derivation can be also decomposed .Lie colour algebra L is complete if and only if its two ideas are both complete .

第二部分首先讨论了若李color代数L可以分解为两个理想的直和，则中心也可以分解为两个理想的直和，而且当中心为零时导子和内导子也有同样的理想直和分解，并且L完备的充要条件是两个理想都完备。

Let be a homeomorphism, the following statements were obtained: if is distal and has POTP ,then does not have the average shadowing property; if is equicontinuous and has the average shadowing property, then f is minimal; let :X→X be distal and chaintransitive, then does not have POTP; is distal if and only if is distal.

设是个同胚映射，得到了如下结果：若有POTP且是distal的，则不具有平均跟踪性；若有平均跟踪性且是等度连续的，则是极小的；若是distal的且是链可迁的，则不具有POTP；是distal的当且仅当是distal的。

A general ring I is a clean general ring if and only if its power series ring is a clean general ring if and only if its skew power series ring is a clean general ring.

1一般环I是一般clean环当且仅当I的形式幂级数环是一般clean环当且仅当I的斜幂级数环是一般clean环。

As applications, we prove the following results: If / has pointwise pseudo-orbit tracing property, for any k ∈ Z+, and fk is chain transitive, then for any k ∈ Z+, fk has open set transitive ; If f has pointwise pseudo-orbit tracing property, and for any n ∈ Z+,fn is chain transitive, then f has sensitive dependence on initial conditions; If f is open set mixing and has pointwise pseudo-orbit tracing property, then f has property P; Let f :→ be a homeomophism, then f is pointwise pseudo-orbit tracing property if and only if the shift map σf is pointwise pseudo-orbit tracing property.

作为应用，证明如下结论：若f具有逐点伪轨跟踪性质，且对任意k∈Z+，fk为链转换的，那么对任意k∈Z+，fk为开集转换；若f具有逐点伪轨跟踪性质，且对任意n∈Z+，fn为链转换的，则f具有初始敏感依赖性质；若f为开集混合的，且具有逐点伪轨跟踪性质，那么f具有性质P；设f：→是同胚映射，那么f具有逐点伪轨跟踪性质当且仅当移位映射σf具有逐点伪轨跟踪性质。

Semantically the sentence involving the construction is ambiguous between a generic reading and an episodic reading, and we propose that its being generic or episodic is determined by the referential/non-referential interpretation of the associated postverbal noun phrase: the sentence is generic if and only if the postverbal noun phrase is interpreted as non-referential, and the sentence is episodic if and only if the postverbal noun phrase is interpreted as referential.

此「V有/呒 NP」谓语结构主要涉及两种语义：指涉恒常的特性，例如「阿明做呒歹志。」；指涉某单一事件的发生，例如「阿明坐呒位。」本论文首先论证吾人可以藉由动词后名词组的有指/无指(referential/non-referential)之语意特性来决定此「V有/呒 NP」谓语的语义。亦即，当名词组有指时，句子涉及某单一事件的发生；当名词组无指时，句子则指涉某恒常的特性。

So get rid of the lone chicken wing and neck; only feed those if, and ONLY IF, they are attached to half of a breast, half of a chicken, or a whole bird.

所以不要单独喂食长长的鸡脖子或鸡翅，但与半个鸡或这整只鸟相连的时候可以食用

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。