如题所述
it is difficult (in) doing sth 这是一个常用句型。
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第1个回答 2009-09-23
It is difficult (in) doing sth.
It is fun (in) doing sth.
It is fun (in) doing sth.
第2个回答 2009-09-27
It is+ difficult (in) doing sth.
It is+形容词+（in）doing sth.
It is+形容词+（in）doing sth.
第3个回答 2009-09-23
加to do sth
