I found difficult to learn English grammar.A it Bthat Cit is

I found difficult to learn English grammar.A it Bthat Cit is I found ( )difficult to learn English grammar I found ____ difficult to learn English grammar. I found that it was frustrating to learn English grammar. I found _____ difficult to english grammar. I found ____ ____ to learn English grammar english is difficult to learn.i like it t_______. She found it difficult to learn English?同意句转换 he found it is difficult to learn english这个说法行不行? I found it difficult to learn English well 同义句 __was difficu i found it difficult to learn english well哪个是宾语 I found that it was difficult to learn English.中that 可以省略吗?