变幻莫测 (biàn huàn mò cè): Unpredictable / ever-changing — Meaning & Stroke Order

The international situation is unpredictable, and diplomats must remain vigilant at all times.

Don't you think her attitude is always unpredictable?

His mood is unpredictable, making it hard to understand.

The stock market is unpredictable, and investors need to be cautious.