1.be careful + about/of+ 名词 注意...的 eg.She is careful about/of her food. =She is careful about/of what she eats. 她很注意饮食.(后面界wh- 从句时,多省略介词) 2.be careful + with + 名词 注意处理... eg.Be careful with the vase; it's valuable. 那花瓶很贵,要小心处理. 此外,还有be caregul (not)to do/that...通常与否定的内容连用 eg.Be careful not to be late. =Be careful (that) you don't be late. 小心不要迟到. (that从句不使用将来时)