Polly Lingual
To Be
开始上课
刽子手
词汇
Vocabulary
be
短语
Phrases
We are
动词变化
Verb Conjugations
非有限
non-finite
动词不定式
infinitive
过去分词
past participle
动名词
gerund
指示
indicative
当前
present
过去
preterite
势在必行
imperative
势在必行
imperative
Related Lessons
To Be (Contractions)
现在时态
Present Tense
祈使语气
Imperative Mood
Simple Past Tense (Irregular Verbs)
Simple Past Tense (Regular Verbs)
课程
Courses
初级
Beginner
语法
Grammar
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