boundaries
词形变化：
同义词：
jump | leap | boundary | limit | going | surround | enclose | spring | bounce | on the way | border | hop | spring back | certain | sure | obliged | forced | border on | touch | be adjacent to | adjoin | vault | skip | on | the | way | destined | recoil | confine | ricochet | trammel | articled | throttle | apprenticed | resile | bounds | restrict | bandaged | reverberate | edge | indentured | saltation | restrain | leaping | rebound |
反义词：