Histopathologically, intraepidermal acantholysis is located at the granular layer in PF and suprabasally in PV.

病理上，落叶性天疱疮表内棘松解位于颗粒细，而寻常性天疱疮则位在基底之上。

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.

类似将附带说放在逗号之间规则，位在句子主要子句之前或之语或从属子句，也应以逗号隔开。