Hxen.com's tips：Every day persisted can learn English well!-->■Learn English Everyday■
infinitive – n. grammar the basic form of a verb
conversation – n. a spoken exchange involving two people or a small group of people
modify – v. grammar: to limit or describe the meaning of (a word or group of words)
tense – n. grammar a form of a verb that is used to show when an action happened
imprecise – n. not clear or exact
phrase – n. a group of two or more words that express a single idea but do not usually form a complete sentence
stuff – n. materials or things
feature – n. the structure, form or appearance of something; a quality
grammar – n. the study of words and their uses in sentences
informal – adj. lacking ceremony; of or related to familiar use
