be from是什么意思？

Nutritionists say only 33% of our calorie intake should be from fat.营养学家说我们所摄入的卡路里中只应有33％来自脂肪。Judging from his accent, he must be from Hunan.从他的口音判断, 他一定是湖南人.This letter must be from Frank; I recognized his scrawl.这封信一定是...

be from的音标：be from的英式发音音标为：[bi: frɔm]be from的美式发音音标为：[bi frʌm]...