1. This sentence ends with a double period.
Consider changing the punctuation.
There is no correct usage for a double period. If the sentence ends with an abbreviation(such as Ave. or p.m.), the final period of the abbreviation serves double duty as the period of the abbreviation serves double duty as the period to end the sentence.
这个句子以双句点结尾。
考虑改变标点符号。
对于双周期没有正确的用法。如果句子以缩写结尾(如Ave.或p.m.)，则缩写的最后一个句点作为双重职责，作为句子结尾的句点作为双重职责。
An ellipsis, used to indicate the omission of a word( or more), consists of three periods usually separated by spaces. When used at the end of a sentence, the ellipsis acts as the final punctuation only when the sentence is deliberately unfinished.
省略，用来表示一个词(或更多)的省略，由三个通常用空格隔开的句点组成。在句末使用省略号时，只有在句子有意未完成时，省略号才充当最后的标点符号。
To indicate that part of a quoted work is missing, a period comes first, followed by a spaced ellipsis.
为了表示引用的部分作品缺失，首先是一个句号，然后是一个间隔的省略号。
2. An article (a, an, or the) is a type of determiner. Possessive adjectives (my, his, our), possessive nouns (Joe's, mother's), and quantifiers(each, every) are also determiners. Single countable nouns usually require a determiner.
冠词(a、An或the)是限定词的一种。所有格形容词(my, his, our)，所有格名词(Joe, mother’s)和量词(each, every)也是限定词。单数名词通常需要限定词。
3. The articles a and an are used with singular nouns to indicate that you’re talking about any member of a particular category (e.g., We saw a dog). The article the can be used with singular or plural nouns to indicate that you’re talking about something specific. We saw the dog suggests that you’re talking about a specific, familiar dog.
冠词a和an与单数名词连用，表示你在谈论某一特定类别的任何成员(例如，We saw a dog)。
冠词the可以和单数名词或复数名词一起使用，表示你在谈论某件具体的事情。We saw the dog暗示你说的是一只特定的，熟悉的狗。