main clause

1.The sentence consists of a main clause and a subordinate clause.

这句中有一个句和一个从句。

2.Similar in principle to the enclosing of parenthetic expressions between commas is the setting off by commas of phrases or dependent clauses preceding or following the main clause of a sentence.

类似将附放在逗号之间规则，位在句句之前或之后片语或从属句，也应以逗号隔开。