它们是有明显区别的.
1,主系表：简单的主系表结构,是由 be+名词或者形容词构成,如：Xiaowei is beautiful. / Langren is a humourous man. 有时表语是一个从句,即表语从句.
2,主谓宾：简单的主谓宾结构,是由行为动词（包括及物动词,动词短语）+名词或者代词.如：I love you. / I surf the net very often. / I go to school every day./ Tom enjoys it .
3, 当主谓宾结构是进行时态时,有的学生容易误解为主系表.如：Xiaowei is wearing a sweater today.这是主谓宾结构的进行时态,
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