而【ér】

而 joins two adjectives, two verb phrases or two clauses in formal writing. What it means depends on how the two halves relate: it contrasts them, it adds one to the other, or it links a cause or means to the action that follows.

Contrast: whereas, but

The most frequent use sets two facts side by side that differ. 而 opens the second clause, before its subject.

Addition: and

Between two adjectives, 而 means "and" and keeps the phrase compact and literary. The adjectives are usually two syllables each.

和 joins nouns, not adjectives that describe something, so this is where learners reach for the wrong word.

• × 他聪明和努力 → 他聪明而努力 / 他又聪明又努力

Cause, purpose or means, then the action

Before a verb, 而 links the action to what drives or shapes it. The first half is usually a phrase with 为, 因, 随 or 根据.

而且, 然而, 反而, 从而 and 而是 are separate words. 因…而 and the first pass at 而 at HSK 4 have their own entries.