At a glance
～上に means "in addition to", "on top of that" or "not only... but also". It adds a second fact that points the same way as the first: both good or both bad.
[Clause A] 上に、[Clause B (often with も)]
このパソコンは軽い上に、値段も安いです。 This computer is light, and on top of that, it's cheap.
How to form it
上に attaches to the plain form of the first clause:
| Attaches to | Form | Example |
|---|---|---|
| Verb | Plain form (dictionary or た-form) + 上に | 道に迷った上に |
| い-adjective | ～い + 上に | 寒い上に |
| な-adjective | ～な / である + 上に | 便利な上に |
| Noun | ～の / である + 上に | 医者である上に |
Register: used in both speech and writing, in polite and casual sentences.