"Thicken the sauce" "inspissate the tar so that it becomes pitch"
"The sauce thickened" "The egg yolk will inspissate"
"thicken the sauce by adding flour"
Oatmeal was used..for thickening soup.
The rain is thickening into sleet.
牛津高阶第八版
美国韦氏词典
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维基百科 (自由的百科全书)