R字母开头的单词或词组(第21页)：
- rewarding
- rhetoric
- rhubarb
- rhinestone
- rib
- ribald
- rhyme
- rickety
- riddle
- rhythmic
- rider
- ridge
- ridicule
- rife
- rifle
- rift
- rig
- robe
- riven
- riot
- ringlet
- rigid
- rile
- rigor
- rind
- riotous
- rite
- ripen
- ripple
- ritual
- rival
- rivalry
- rive
- rivet
- riveting
- rivulet
- rudimentary
- rumple
- robust
- ruminant
- roster
- roe
- roil
- rookie