新概念英語第一冊89-90課課文知識點 further notes on the text
1．i believe that this house is for sale. 我想這房子是要新概念的吧！
believe是“相信”、“認為”的意思，后可跟某人或名詞性從句。如：
i believe you. 我相信你（說的話）。
i believe that he has already gone to london. 我認為他已經去倫敦了。
for sale意為“供新概念”、“待售”。
2．how long have you lived here? 您在這里住了多長時間？
how long常用于詢問時間的長短與物體的長度。
3．since 1976, 從 1976年起。
這是介詞短語，since在這里是介詞。用這個介詞短語作時間狀語的句子中，謂語要用完成時。（請參見本課語法部分。）
4．how much does this house cost? 這座房子賣多少錢？
how much常用于詢問東西的新概念。 cost是指得到一件東西所花費的錢，其真正的價值可能低于或高于所要的價。這種新概念主要是指商店內的標價或貨主索要的新概念。相比之下，worth (prep.)主要是指某物的本身價值。
5．…i can't decide yet．……我還不能決定。
句中的yet常見于否定句，表示“迄今仍未”的意思。
新概念英語第一冊89-90課語法知識點 grammar in use
for與 since
現在完成時還可以描述發(fā)生在過去且一直延續(xù)到現在的動作，這種動作甚至有可能延續(xù)下去。在這種情況下，它一般與for+ 一段時間、since+ 某個時間點連用。
請注意：for+ 一段時間表示某個動作持續(xù)多長時間；since+ 某個時間點表示某個動作是何時開始的。
新概念英語第一冊89-90課詞匯學習 word study
1．retire v.
（1）退休；離職：
he retired at the age of 60. 他60歲時退休了。
he's going to retire soon from the sea. 不久他將退休，結束其航海生涯。
（2）退出；退隱：
he often retires to his country house at weekends. 他周末通常到他那個鄉(xiāng)間別墅生活。
the ladies retired, and the gentlemen went on drinking and chatting. 女士們離席退出，先生們則繼續(xù)喝酒聊天。
2．worth prep.
（1）相當于……價值，值……錢：
the new house would be worth 50, 000 pounds. 這座新房子會值50，000英鎊。
how much is the necklace worth? 這條項鏈值多少錢？
（2）具有……價值；值得：
that city is worth visiting. 那座城市值得一游。
is the film worth seeing? 這部電影值得一看嗎？
新概念英語第一冊90課課后練習答案 key to written exercises
lesson 90
a
1 did the sun set at twenty past seven?
the sun didn't set at twenty past seven.
2 did he eat his lunch at one o'clock?
he didn't eat his lunch at one o'clock.
3 did they do their homework last night?
they didn't do their homework last night.
4 did he come by car this morning?
he didn't come by car this morning.
5 did the sun rise at half past five?
the sun didn't rise at half past five.
6 did you swim across the river yesterday?
we didn't swim across the river yesterday.
b
1 yes, i did my homework last night.
he hasn't done his homework yet.
2 yes, mrs. jones went to the butcher's this morning.
mrs. williams hasn't been to the butcher's yet.
3 yes, i spoke to him yesterday.
she hasn't spoken to him yet.
4 yes, george swam across the river an hour ago.
sam hasn't swum across it yet.
5 yes, i saw that film yesterday.
sam and penny haven't seen that film yet.
6 yes, tim took off his shoes a minute ago.
frank hasn't taken off his shoes yet.
1．i believe that this house is for sale. 我想這房子是要新概念的吧！
believe是“相信”、“認為”的意思，后可跟某人或名詞性從句。如：
i believe you. 我相信你（說的話）。
i believe that he has already gone to london. 我認為他已經去倫敦了。
for sale意為“供新概念”、“待售”。
2．how long have you lived here? 您在這里住了多長時間？
how long常用于詢問時間的長短與物體的長度。
3．since 1976, 從 1976年起。
這是介詞短語，since在這里是介詞。用這個介詞短語作時間狀語的句子中，謂語要用完成時。（請參見本課語法部分。）
4．how much does this house cost? 這座房子賣多少錢？
how much常用于詢問東西的新概念。 cost是指得到一件東西所花費的錢，其真正的價值可能低于或高于所要的價。這種新概念主要是指商店內的標價或貨主索要的新概念。相比之下，worth (prep.)主要是指某物的本身價值。
5．…i can't decide yet．……我還不能決定。
句中的yet常見于否定句，表示“迄今仍未”的意思。
新概念英語第一冊89-90課語法知識點 grammar in use
for與 since
現在完成時還可以描述發(fā)生在過去且一直延續(xù)到現在的動作，這種動作甚至有可能延續(xù)下去。在這種情況下，它一般與for+ 一段時間、since+ 某個時間點連用。
請注意：for+ 一段時間表示某個動作持續(xù)多長時間；since+ 某個時間點表示某個動作是何時開始的。
新概念英語第一冊89-90課詞匯學習 word study
1．retire v.
（1）退休；離職：
he retired at the age of 60. 他60歲時退休了。
he's going to retire soon from the sea. 不久他將退休，結束其航海生涯。
（2）退出；退隱：
he often retires to his country house at weekends. 他周末通常到他那個鄉(xiāng)間別墅生活。
the ladies retired, and the gentlemen went on drinking and chatting. 女士們離席退出，先生們則繼續(xù)喝酒聊天。
2．worth prep.
（1）相當于……價值，值……錢：
the new house would be worth 50, 000 pounds. 這座新房子會值50，000英鎊。
how much is the necklace worth? 這條項鏈值多少錢？
（2）具有……價值；值得：
that city is worth visiting. 那座城市值得一游。
is the film worth seeing? 這部電影值得一看嗎？
新概念英語第一冊90課課后練習答案 key to written exercises
lesson 90
a
1 did the sun set at twenty past seven?
the sun didn't set at twenty past seven.
2 did he eat his lunch at one o'clock?
he didn't eat his lunch at one o'clock.
3 did they do their homework last night?
they didn't do their homework last night.
4 did he come by car this morning?
he didn't come by car this morning.
5 did the sun rise at half past five?
the sun didn't rise at half past five.
6 did you swim across the river yesterday?
we didn't swim across the river yesterday.
b
1 yes, i did my homework last night.
he hasn't done his homework yet.
2 yes, mrs. jones went to the butcher's this morning.
mrs. williams hasn't been to the butcher's yet.
3 yes, i spoke to him yesterday.
she hasn't spoken to him yet.
4 yes, george swam across the river an hour ago.
sam hasn't swum across it yet.
5 yes, i saw that film yesterday.
sam and penny haven't seen that film yet.
6 yes, tim took off his shoes a minute ago.
frank hasn't taken off his shoes yet.