HSK 3
Wǒ xūyào qù yínháng huàn wàihuì.
I need to go to the bank to exchange foreign currency.
HSK 4
Wàihuì shìchǎng měitiān jiāoyìliàng hěn dà.
The forex market has huge daily trading volume.
HSK 7-9
Zhōngguó yǒu dàliàng de wàihuì chǔbèi.
China has large foreign exchange reserves.