My brother has lots of friends in Beijing.
＊＊a lot of = lots of 所以这是没问题是
My brother has many many friends in Beijing.
＊＊这是表明真的很多,但如果这是课业,答案一定不是这个,但日常口语可以使用.
My brother has loads of friends in Beijing.
＊＊loads of 这个是比 lots of 夸张一点点的说法
以上3个语法都是正确的
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