幾個基本時態(tài)標志詞：

　　一、一般現(xiàn)在時：

　　標志：always, usually, often, sometimes, every week (day, year, month…), once a week, on Sundays,

　　結(jié)構(gòu)：①be動詞；②行為動詞

　　二、一般過去時：

　　標志：ago, yesterday, the day before yesterday, last week(year, night, month…), just now, at the age of 5, one day, long long ago, once upon a time, etc.

　　結(jié)構(gòu)：①be動詞；②行為動詞

　　三、現(xiàn)在進行時：

　　標志：now, at this time, these days, etc.

　　結(jié)構(gòu)：am/is/are+doing

　　四、過去進行時：

　　標志：at this time yesterday, at that time或以when引導(dǎo)的謂語動詞是一般過去時的時間狀語等。

　　結(jié)構(gòu)：was/were+doing

　　五、現(xiàn)在完成時：

　　標志：recently, lately, since…for…,in the past few years, etc.

　　結(jié)構(gòu)：have/has + done

　　六、過去完成時：

　　標志：before,by,the end of last year(term,month)......

　　結(jié)構(gòu)：had done