Usages of shīféi
今天 不用 施肥。jīntiān búyòng shīféi.
There is no need to fertilize today.
一旦 叶片 发黄， 就 先 不用 施肥。yídàn yèpiàn fāhuáng, jiù xiān búyòng shīféi.
Once the leaves turn yellow, do not fertilize for the moment.
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