粗茶淡饭

cū chá dàn fàn

simple, plain food

Character by character

粗cū
coarse

茶chá
tea

淡dàn
plain

饭fàn
rice

爷爷一辈子粗茶淡饭，身体反而很硬朗。

Grandpa's eaten plain food all his life, yet he's as fit as a fiddle.

Tone: neutral.

Also a humble host's phrase: 只有些粗茶淡饭.

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