After Checking the Rules, Here’s What They Say 上で・によると・なぜなら

These forms help connect a statement to its circumstances or evidence. Verb + 上で means “after doing” or “in doing,” depending on whether it marks sequence or a condition for an action. によると and によれば cite a source for reported information. なぜなら introduces an explanation, usually followed by から or ため. The distinction is useful in instructions, reports, and clear explanations.

Verb past form + 上で can mean “after doing X, then Y,” with a deliberate sequence. Noun + の上で means “in terms of” or “from the standpoint of.” It often signals that the following action should be taken only after the first step is complete.

によると and によれば introduce the source of information. They commonly pair with reported forms such as そうだ or ということだ. They cite where the information came from; they do not by themselves prove that the report is true.

なぜなら puts the reason after the claim, often at the beginning of a new sentence. It usually pairs with から or ため at the end of the explanation, giving the sentence a clear, written structure.

Vocabulary