1、Our world is in danger.The greenhouse effect may cause the level ofthe sea to rise and flood cities and even the whole ______________.(country) 是country还是countries,为什么?2、Tom has great ___________ incollecting stamps and travelling around the world.(interesting) 是interest还是interests,为什么?

1. Country. 前面淹没城市，一个国家有很多城市， 因此是复数。但后面，甚至淹没，这整个国家，单数形式。

2. have interest in  固定词组搭配  interest 不可数名词

1、Our world is in danger. The greenhouse effect may cause the level ofthe sea to rise and flood cities and even the whole ______________. (country)
是country还是countries，为什么？
选country。因为the whole country是【一个完整的国家】，意思是：“整个国家/全国”
2、Tom has great ___________ in collecting stamps and travelling around the world. (interesting)
是interest还是interests，为什么？
选interest。因为have interest in collecting stamps and travelling around the world是【兴趣爱好】的固定短语。

countries 因为这句话可以从这里flood cities and even the whole ______________.得出,flood这里是动词 淹没城市 甚至整个国家.city城市复数形式,表示并列 country国家也用复数形式
第二题 interest
固定短语 have interest in 在.感兴趣
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