VOA慢速英语:US Allies Support Airstrikes on Syrian Military Targets

deter – v. prevent from happening

slaughter – v. to kill a lot of people in a violent way

conventional - adj. of a kind that has been around for a long time and is considered to be usual or typical​

escalate - v. to become worse or to make (something) worse or more severe​

concrete – adj. relating to something real, rather than general ideas or qualities

reckless – adj. doing something dangerous or carelessly

unilateral – adj. involving only one group or country

alternative – adj. a different choice or available option