8B Unit1導(dǎo)學(xué)案及教案1
(2 ) 現(xiàn)在完成時常見兩種句型：
① 主語＋have / has been＋for 短語/ since 短語
② it is＋一段時間＋ since 從句
例如： he has been in the league for three years.
= it is three years since he joined the league. 他入團(tuán)已三年了。
請嘗試著做以下的練習(xí)
1. i _____________ (work) here since i __________ (move) here in 1999.
2. ---how long ____ __ the smiths ________(stay) here? --- for two weeks.
3. she ____________ (be) ill for three days.
4. she____________ (not read) this book before.
5. __ __ you ever __________ (travel) on a train before?
3. a. for 和表示一段時間的詞組連用。
eg. for six hours/nine days/ two weeks/thirty years
b. since 和表示過去某一時刻的詞或詞組連用，這是介詞。
eg. since nine o’clock this morning / last summer/ three weeks ago/september
since 還可以引導(dǎo)時間狀語從句，表示“自從…..以來”，這是連詞。
eg. 自從他出生以來，他就住在這兒。he has lived here since he was born.
______ three months ______ two weeks ago, _______ 1998, ______last sunday
4、延續(xù)性動詞和終止性動詞的概念
英語中，動詞按其動作發(fā)生的方式、動作發(fā)生過程的長短，可分為延續(xù)性動詞和終止性動詞。
延續(xù)性動詞表示能夠延續(xù)的動作，這種動作可以延續(xù)下去或產(chǎn)生持久影響。如：learn, work, stand, lie, know, walk, keep, have, wait, watch, sing, read, sleep, live, stay等。
終止性動詞也稱非延續(xù)性動詞、瞬間動詞或短暫性動詞，表示不能延續(xù)的動作，這種動作發(fā)生后立即結(jié)束。如open, close, finish, begin, come, go, arrive, reach, get to, leave, move, borrow, buy等。
5、延續(xù)性動詞的用法特征
a. 延續(xù)性動詞可以用于現(xiàn)在完成時，其完成時態(tài)可與表示"段時間"的狀語連用。表示"段時間"的短語有：for two years, during the past three years, since last year, how long等。如：i have learned english since i came here.自從我來到這兒就學(xué)英語了。
b. 延續(xù)性動詞不能與表示短暫時間的"點時間"狀語連用。如：it raind at eight yesterday morning.(誤) rain為延續(xù)性動詞，而at eight表示"點時間"，前后顯然矛盾。如果用延續(xù)性動詞表示一瞬間的動作，可以借助come, begin, get等終止性動詞來表示。上句可改為：it began to rain at eight yesterday morning.(正)又如：
-when did you get to know jack? -two years ago.
-then you’ve known each other for more than two years. -that’s right.
6、終止性動詞的用法特征
a. 終止性動詞可用來表示某一動作完成，因此可用于現(xiàn)在完成時。如：