be sure about和make sure的意思和用法差别。make sure透露表现“弄的确；核实；查证”。be sure＋about+动名词或名词，意为“确信……”；“对……有掌握”。make sure后可加从句或动词不定式，be sure about后只能加名词、代词或动名词。
I make sure I make time for fishing because it's how I de-stress。
It is impossible to be sure about the value ofland。
Be sure to give your family my regards.
No one knows for sure what happened.
She seems very sure of herself.
He is intelligent, to be sure, but he's also very lazy.