【初中英语阅读—说明文】Robots主题 “be able to与can的区别”

①be able to/can的区别

“Can” is used in the present tense. It is used to talk about our ability to do things.

“Be able to” is also possible in these cases; however, it sounds a bit more formal here.

（更正式）

e.g.

--She can speak English well.

  她英语讲得很好。

--She is able to speak English well.

  她英语讲得很好。

To talk about things that we managed to do on specific occasions in the past, we cannot use could. Instead, we use was/were able to. The verb managed, succeeded (in…v+ing) are also possible in this case.（在过去的特定场景下，不能用could，只能用was able to）

e.g.

--I was able to get some really good bargains in the sale.

 (NOT I could get some really good bargains in the sale.) 

 我能在打折时，买到不错的便宜货。

②either…or…

We use “either… or…” to connect items which are the same grammatical type, e.g. words, phrases, clauses.

e.g.

--I’ve saved some money to buy either a DVD player or an MP3 player.

我存了些钱，要么买一个DVD，要么买MP3。

--You can stay either with me or with Janet.

你可以和我或者Janet呆在一起。

--Either I drive to the airport or I get a taxi.

要么我开车去机场，或者打出租车去。