严重 / 严厉 / 严格【yánzhòng / yánlì / yángé】

严重, 严厉 and 严格 all start with 严, and English often translates two of them as "severe" or "strict". 严重 describes how bad a situation is, 严格 how high a standard is, and 严厉 how hard a person's manner is.

严重 – how bad

严重 goes with problems, mistakes, damage and pollution. It describes a situation, not a person's character. As an adverb it means "badly": 严重影响, 严重破坏.

严格 or 严厉

Both describe a teacher or a parent, and they say different things. 严格 is about standards: the person expects a lot and lets nothing slide. 严厉 is about tone: the person is stern, and the criticism stings.

严格 is often praise; 严厉 rarely is. 严格 also goes with rules and checks – 严格遵守, 严格检查 – where 严厉 would be wrong. 严厉 goes with punishment and criticism: 严厉的处罚.

Mixing them up

• × 我的老师很严重 → 我的老师很严格
• × 这个错误很严格 → 这个错误很严重
• × 严厉遵守规定 → 严格遵守规定