Remembering vocabulary through roots, prefixes and suffixes

Most academic English is assembled from meaningful Latin and Greek pieces. Recognise the piece and you can guess the word without a dictionary.

Prefixes bend the meaning

• un-, in-, im-, dis- negate: *unhappy*, *invisible*, *impossible*, *disagree*
• re- repeats: *rewrite*, *return*, *review*
• pre- comes before: *preview*, *predict*, *prepare*
• over- / under- too much / too little: *overwork*, *underestimate*

Suffixes tell you the part of speech

This is the piece Vietnamese speakers skip most, because Vietnamese words do not inflect:

• -tion, -ment, -ness → noun: *decision*, *agreement*, *happiness*
• -able, -ful, -ous → adjective: *reliable*, *helpful*, *dangerous*
• -ly → adverb: *quickly*, *carefully*

The ending alone tells you where the word belongs in a sentence.

Roots worth learning first

• spect (to look): *inspect*, *respect*, *spectator*
• port (to carry): *export*, *transport*, *portable*
• dict (to say): *predict*, *dictionary*, *contradict*

Meet *contradict* for the first time knowing *contra-* is "against" and *dict* is "say", and the meaning arrives on its own. That is how a vocabulary compounds.