stopsb.fromdoingsth=preventsb.fromdoingsth=keepsb.fromdoingsth.意为:阻止某人做某事,其中前两个短语中的from可略,意思不变,而最后一个短语中的from不可略,略去后意为:坚持做某事.protectsb.fromdoingsth.意为保护某人免受.....的伤害,且from不可略。例:Weshouldprotectourskinfrombeingburntinsummer.