| A | B | 
| exclaim | say suddenly with strong feeling | 
| exclamation | interjection | 
| detain | hold back | 
| detention | keeping in custody | 
| comprehend | understand | 
| comprehension | ability to get the meaning | 
| intrude | force oneself in | 
| intrusion | coming unasked and unwanted | 
| ferocious | fierce | 
| ferocity | savage cruelty | 
| sustain | keep going | 
| sustenance | nourishment | 
| pertain | connected as a part | 
| pertinent | to the point | 
| commit | pledge;  do or perform | 
| commission | percentage of amount of business done | 
| recede | move backward | 
| recession | period of temporary business reduction | 
| invade | enter as if to take posession | 
| invasion | entering by force as an enemy |