Zhíliú yǔ jiāoliú shì liǎng zhǒng bùtóng de diànliú xíngshì.
DC and AC are two different forms of electrical current.
Tips
memory
直 means 'straight/direct' and 流 means 'flow' — direct current flows straight in one direction, unlike alternating current (交流, jiāoliú) which alternates.
