强化训练17 语法填空(三)
(45分钟，100分)
A
A triathlon (三项全能运动) is a sports event which combines three sports, __1__ (typical) running, biking, and swimming. During a triathlon, athletes finish all three sports without stopping __2__ (beat) the clock. People of all ages and sizes can compete in triathlons. But much like other sports events, a lot of professional __3__ (compete) rule the triathlon world. In addition, many triathlons __4__ (hold) to benefit charity, much like marathons.
