I+think+about+playing+baseball+is+interesting有错吗?

您好，I think about playing baseball is interesting. 中的介词 about 是不需要的，因为 playing baseball is interesting 本身就是一个宾语从句，其中 playing baseball 是动名词词组充当宾语从句的主语，interesting 是现在分词作形容词，在宾语从句中充当表语，所以宾语从句是（主系表）结构，而宾语从句引导词 that 省略了。所以完整句子是：
I think (that) playing baseball is interesting.
第一层次：
I think something.（something 作 think 的宾语）
主语 = I
谓语 = think
宾语 = something

第二层次：
I think that .....（that 引导宾语从句，替代 something，作 think 的宾语）
主句主语 = I
主句谓语 = think
主语宾语 = 由 that 引导的宾语从句

第三层次：
I think (that) playing baseball is interesting.
(that) playing baseball is interesting 是宾语从句，that 不做成分，可以省略。
宾语从句主语 = playing baseball
宾语从句谓语 = is（be 系动词）
宾语从句表语 = interesting
所以主句 = 主谓宾；从句 = 主系表。

这个句子想表达：我认为打篮球很有趣/好玩。动词think的意思是“认为”。
但这个句子有错，错在在动词think后不应该加介词about, 因为动词短语think about的意思是“考虑”，例如：
I am thinking about the plan. 我正在考虑这个计划。

扩展阅读：thank you all the same ... what do you think about ... you complete me ... think about doing sth ... i ll think about it ... i m crazy about you ... that is all right ... get out of the way ... you are welcome ...